222 files changed, 2704 insertions, 0 deletions
diff --git a/40/CH10/EX10.10/Exa_10_10.sce b/40/CH10/EX10.10/Exa_10_10.sce
new file mode 100755
index 000000000..7ed13d3ec
--- /dev/null
+++ b/40/CH10/EX10.10/Exa_10_10.sce
@@ -0,0 +1,12 @@
+//Maximally flat FIR filter design
+Fp=0.2;
+Fs=0.4;
+Fc=0.3;
+Ft=0.2;
+N0=1+0.5/Ft^2;
+N0=ceil(N0);
+alpha=(cos(%pi*Fc))^2;
+k=5;Mmin=14;
+L=Mmin-k;
+N=2*Mmin-1;
+disp(N,'Hence with this length we can get maximally flat FIR filter with no ripples in passband');
+\ No newline at end of file
diff --git a/40/CH10/EX10.2/Exa_10_2.sce b/40/CH10/EX10.2/Exa_10_2.sce
new file mode 100755
index 000000000..f81083bd9
--- /dev/null
+++ b/40/CH10/EX10.2/Exa_10_2.sce
@@ -0,0 +1,23 @@
+//Truncation and Windowing
+//(a)N=9,Barlett Window.
+z=%z;
+Fc=0.25;
+n=-4:4;
+hn=2*Fc*(sinc(0.5*n'*%pi))
+Wn=1-(2*abs(n'))/8//Barlett window
+hwn=hn.*Wn
+Hcz=0;
+for i=1:length(hwn)
+     Hcz=Hcz+hwn(i)*(z^((2-i)));
+end
+Hcz//indicates delay of 0.15ms
+//(b)N=6,vonhann Window
+n1=-2.5:2.5;
+hn1=2*Fc*(sinc(0.5*n1'*%pi))
+Wn1=0.5+0.5*(cos(0.4*%pi*n1'))//Vonhann window
+hwn1=hn1.*Wn1
+Hcz1=0;
+for i=1:length(hwn1)
+     Hcz1=Hcz1+hwn1(i)*(z^((2-i)));
+end
+Hcz1//1st sample of hwn is 0 hence delay is 1.5ms
+\ No newline at end of file
diff --git a/40/CH10/EX10.3ab/Exa_10_3ab.sce b/40/CH10/EX10.3ab/Exa_10_3ab.sce
new file mode 100755
index 000000000..f2ecda005
--- /dev/null
+++ b/40/CH10/EX10.3ab/Exa_10_3ab.sce
@@ -0,0 +1,50 @@
+//FIR filter design using windows
+//(a)Design of FIR filter to meet following specifications
+fp=2;fs=4;Ap=2;As=40;S=20;
+Fp=fp/S;Fs=fs/S;
+Fc=0.15;
+z=%z;
+N1=3.21/(Fs-Fp);
+N1=ceil(N1)
+N2=5.71/(Fs-Fp);
+N2=ceil(N2)
+n1=-16:16;
+n2=-28.5:1:28.5;
+hn1=2*Fc*(sinc(2*Fc*n1'));
+hn2=2*Fc*(sinc(2*Fc*n2'));
+Wn1=0.5+0.5*(cos(2*%pi*n1'/(N1-1)));//Vonhann window
+Wn2=0.42+0.5*(cos(2*%pi*n2'/(N2-1)))+0.08*(cos(4*%pi*n2'/(N2-1)));//Blackman window
+hwn1=abs(hn1.*Wn1);
+hwn2=abs(hn2.*Wn2);
+[hwn1F,fr1]=frmag(hwn1,256);
+[hwn2F,fr2]=frmag(hwn2,256);
+hwn1F1=20*log10(hwn1F);
+hwn2F1=20*log10(hwn2F);
+plot2d(fr1,hwn1F1);
+plot2d(fr2(1:length(fr2)-2),hwn2F1(1:length(fr2)-2));
+xlabel('Digital frequency');
+ylabel('Magnitude [dB]');
+title('Low pass filter using vonhann and Blackmann windows Fc=0.15,vonhann N=33,Blackman N=58');
+//(b)Minimum length design
+Fcv=0.1313;
+Fcb=0.1278;
+Nv=23;Nb=29;
+nv=-11:11;
+nb=-14:14;
+hnv=2*Fcv*(sinc(2*Fcv*nv'));
+hnb=2*Fcb*(sinc(2*Fcb*nb'));
+Wnv=0.5+0.5*(cos(2*%pi*nv'/(Nv-1)));//Vonhann window
+Wnb=0.42+0.5*(cos(2*%pi*nb'/(Nb-1)))+0.08*(cos(4*%pi*nb'/(Nb-1)));//Blackman window
+hwnv=abs(hnv.*Wnv);
+hwnb=abs(hnb.*Wnb);
+[hwnvF,frv]=frmag(hwnv,256);
+[hwnbF,frb]=frmag(hwnb,256);
+hwnvF=20*log10(hwnvF);
+hwnbF=20*log10(hwnbF);
+b=gca();
+xset('window',2);
+plot(frv,hwnvF);
+plot(frb,hwnbF);
+xlabel('Digital frequency');
+ylabel('Magnitude [dB]');
+title('Vonhann Fc=0.1313,Minimum N=23,Blackmann Fc=0.1278,Minimum N=29');
+\ No newline at end of file
diff --git a/40/CH10/EX10.3ab/Exa_10_3ab_0.jpg b/40/CH10/EX10.3ab/Exa_10_3ab_0.jpg
new file mode 100755
index 000000000..5253796af
--- /dev/null
+++ b/40/CH10/EX10.3ab/Exa_10_3ab_0.jpg
diff --git a/40/CH10/EX10.3ab/Exa_10_3ab_1.jpg b/40/CH10/EX10.3ab/Exa_10_3ab_1.jpg
new file mode 100755
index 000000000..5f84164f1
--- /dev/null
+++ b/40/CH10/EX10.3ab/Exa_10_3ab_1.jpg
diff --git a/40/CH10/EX10.3cd/Exa_10_3cd.sce b/40/CH10/EX10.3cd/Exa_10_3cd.sce
new file mode 100755
index 000000000..0a2e92043
--- /dev/null
+++ b/40/CH10/EX10.3cd/Exa_10_3cd.sce
@@ -0,0 +1,37 @@
+//Design of high pass FIR filter with specifications
+//fp=4kHZ;fs=2kHZ;Ap=2dB;As=40dB
+fp=2;fs=4;Ap=2;As=40;S=20;
+Fp=fp/S;Fs=fs/S;
+Ft=0.1;
+Fc=0.15
+N1=3.47/(Fs-Fp);//hamming
+N1=int(N1)+1
+N2=5.71/(Fs-Fp);//blackman
+N2=int(N2)+1
+[hn1]=eqfir(N1,[0 0.1;0.2 0.5],[0 1],[1 1]);
+[HF1,fr1]=frmag(hn1,512);
+Hf1=20*log10(HF1);
+[hn2]=eqfir(58,[0 0.1;0.2 0.43],[0 1],[1 1]);
+[HF2,fr2]=frmag(hn2,512);
+Hf2=20*log10(HF2);
+a=gca();
+plot2d(fr1,Hf1,rect=[0 -120 0.5 4]);
+plot2d(fr2(1:length(fr2)-5),Hf2(1:length(fr2)-5),rect=[0 -120 0.5 4]);
+xlabel('Digital Frequency F');
+ylabel('Magnitude [dB]');
+xtitle('High pass filter using Hamming and Blackmann windows LPP Fc=0.35');
+//Minimum Length Design
+[hn3]=eqfir(22,[0 0.1;0.2 0.43],[0 1],[1 1]);
+[HF3,fr3]=frmag(hn3,512);
+Hf3=20*log10(HF3);
+[hn4]=eqfir(29,[0 0.1;0.2 0.5],[0 1],[1 1]);
+[HF4,fr4]=frmag(hn4,512);
+Hf4=20*log10(HF4);
+xset('window',1);
+a=gca();
+plot2d(fr3(1:length(fr3)-5),Hf3(1:length(fr3)-5),rect=[0 -120 0.5 4]);
+plot2d(fr4,Hf4,rect=[0 -120 0.5 4]);
+xlabel('Digital Frequency F');
+ylabel('Magnitude [dB]');
+xtitle('Hamming LPP Fc=0.3293 N=22;Blackmann LPP Fc=0.3277 N=29');
+
diff --git a/40/CH10/EX10.3cd/Exa_10_3cd_0.jpg b/40/CH10/EX10.3cd/Exa_10_3cd_0.jpg
new file mode 100755
index 000000000..ad2546975
--- /dev/null
+++ b/40/CH10/EX10.3cd/Exa_10_3cd_0.jpg
diff --git a/40/CH10/EX10.3cd/Exa_10_3cd_1.jpg b/40/CH10/EX10.3cd/Exa_10_3cd_1.jpg
new file mode 100755
index 000000000..c4a0af20e
--- /dev/null
+++ b/40/CH10/EX10.3cd/Exa_10_3cd_1.jpg
diff --git a/40/CH10/EX10.4a/Exa_10_4.sce b/40/CH10/EX10.4a/Exa_10_4.sce
new file mode 100755
index 000000000..7880882ab
--- /dev/null
+++ b/40/CH10/EX10.4a/Exa_10_4.sce
@@ -0,0 +1,29 @@
+//Half band FIR Filter Design
+//(a)lowpass Half band Filter
+s=%s;z=%z;
+fp=8;fs=16;Ap=1;As=50;
+S=2*(fs+fp);
+Fp=fp/S;Fs=fs/S;Fc=0.25;
+delp=(10^(Ap/20)-1)/(10^(Ap/20)+1);
+dels=10^(-As/20);
+del=min(delp,dels);
+As0=-20*log10(del)
+N1=(As0-7.95)/(14.36*(Fs-Fp))+1;
+N1=int(N1)+1;
+B=0.0351*(As0-8.7)
+[hn1]=eqfir(19,[0 1/6;1/3 0.5],[1 0],[1 1]);
+[HLPF1,fr1]=frmag(hn1,512);
+HLPf1=20*log10(HLPF1);
+a=gca();
+plot2d(fr1,HLPf1);
+xlabel('Digital Frequency');
+ylabel('Magnitude in dB');
+xtitle('Kaiser half band LPF:B=1.44;Fc=0.25');
+[hn2]=eqfir(21,[0 1/6;1/3 0.5],[1 0],[1 1]);
+[HLPF2,fr2]=frmag(hn2,512);
+HLPf2=20*log10(HLPF2);
+xset('window',1);
+plot2d(fr2,HLPf2);
+xlabel('Digital Frequency');
+ylabel('Magnitude in dB');
+xtitle('Hamming half-band LPF:N=21;Fc=0.25');
diff --git a/40/CH10/EX10.4a/Exa_10_4a_0.jpg b/40/CH10/EX10.4a/Exa_10_4a_0.jpg
new file mode 100755
index 000000000..8bed5403a
--- /dev/null
+++ b/40/CH10/EX10.4a/Exa_10_4a_0.jpg
diff --git a/40/CH10/EX10.4a/Exa_10_4a_1.jpg b/40/CH10/EX10.4a/Exa_10_4a_1.jpg
new file mode 100755
index 000000000..4a1f71522
--- /dev/null
+++ b/40/CH10/EX10.4a/Exa_10_4a_1.jpg
diff --git a/40/CH10/EX10.4b/Exa_10_4b.sce b/40/CH10/EX10.4b/Exa_10_4b.sce
new file mode 100755
index 000000000..78ad4cb2d
--- /dev/null
+++ b/40/CH10/EX10.4b/Exa_10_4b.sce
@@ -0,0 +1,30 @@
+//Half band FIR Filter Design
+//(a)band-stop Half band Filter
+s=%s;z=%z;
+fp1=1;fs1=2;fp2=4;fs2=3;Ap=1;As=50;
+S=2*(fs1+fs2);
+Fp=0.5*(fs2/S-fs1/S);Fs=0.5*(fp2/S-fp1/S);
+Fc=0.5*(Fp+Fs);Fo=0.25;
+delp=(10^(Ap/20)-1)/(10^(Ap/20)+1);
+dels=10^(-As/20);
+del=min(delp,dels);
+As0=-20*log10(del)
+N1=(As0-7.95)/(14.36*(Fs-Fp))+1;
+N1=ceil(N1);
+B=0.0351*(As0-8.7)
+[hn1]=eqfir(31,[0 0.1;0.2 0.3;0.4 0.5],[1 0 1],[1 1 1]);
+[HBSF1,fr1]=frmag(hn1,400);
+HBSf1=20*log10(HBSF1);
+a=gca();
+plot2d(fr1,HBSf1);
+xlabel('Digital Frequency');
+ylabel('Magnitude in dB');
+xtitle('Kaiser half band LPF:B=1.44;Fc=0.25');
+[hn2]=eqfir(35,[0 0.1;0.2 0.3;0.4 0.5],[1 0 1],[1 1 1]);
+[HF2,fr2]=frmag(hn2,200);
+HBSf2=20*log10(HF2);
+xset('window',1);
+plot2d(fr2,HBSf2);
+xlabel('Digital Frequency');
+ylabel('Magnitude in dB');
+xtitle('Hamming half-band LPF:N=21;Fc=0.25');
diff --git a/40/CH10/EX10.4b/Exa_10_4b_0.jpg b/40/CH10/EX10.4b/Exa_10_4b_0.jpg
new file mode 100755
index 000000000..0e45c2fee
--- /dev/null
+++ b/40/CH10/EX10.4b/Exa_10_4b_0.jpg
diff --git a/40/CH10/EX10.4b/Exa_10_4b_1.jpg b/40/CH10/EX10.4b/Exa_10_4b_1.jpg
new file mode 100755
index 000000000..a54d96aae
--- /dev/null
+++ b/40/CH10/EX10.4b/Exa_10_4b_1.jpg
diff --git a/40/CH10/EX10.5a/Exa_10_5a.jpg b/40/CH10/EX10.5a/Exa_10_5a.jpg
new file mode 100755
index 000000000..225001878
--- /dev/null
+++ b/40/CH10/EX10.5a/Exa_10_5a.jpg
diff --git a/40/CH10/EX10.5a/Exa_10_5a.sce b/40/CH10/EX10.5a/Exa_10_5a.sce
new file mode 100755
index 000000000..42d0cbf29
--- /dev/null
+++ b/40/CH10/EX10.5a/Exa_10_5a.sce
@@ -0,0 +1,32 @@
+//Fir low pass filter design by frequency sampling
+z=%z;
+N=10;
+magHk=[1 1 1 0 0 0 0 0 1 1];
+k=[0:7 -1 -2];
+fik=-%pi*k'*(N-1)/N;
+for i=1:length(fik)
+    H1k(i)=magHk(i)*exp(%i*fik(i));
+end
+H1n=(dft(H1k,1));
+H2k=H1k;
+H2k(3)=0.5*%e^(-%i*1.8*%pi);
+H2k(9)=0.5*%e^(%i*1.8*%pi);
+H2n=(dft(H2k,1));
+H1Z=0;H2Z=0;
+for i=1:length(H1n)
+    H1Z=H1Z+H1n(i)*z^(-i); 
+end
+for i=1:length(H2n)
+    H2Z=H2Z+H2n(i)*z^(-i); 
+end
+F=0:0.01:1;
+F1=0:0.1:0.9;
+H1F=abs(horner(H1Z,exp(%i*2*%pi*F')));
+H2F=abs(horner(H2Z,exp(%i*2*%pi*F')));
+a=gca();
+plot2d(F1,magHk);
+plot2d(F,H2F);
+plot2d(F,H1F);
+xlabel('Digital Frequency F');
+ylabel('magnitude');
+xtitle('Low pass filter using frequency sampling');
+\ No newline at end of file
diff --git a/40/CH10/EX10.5b/Exa_10_5b.jpg b/40/CH10/EX10.5b/Exa_10_5b.jpg
new file mode 100755
index 000000000..889ef2ec6
--- /dev/null
+++ b/40/CH10/EX10.5b/Exa_10_5b.jpg
diff --git a/40/CH10/EX10.5b/Exa_10_5b.sce b/40/CH10/EX10.5b/Exa_10_5b.sce
new file mode 100755
index 000000000..7a3f04ee9
--- /dev/null
+++ b/40/CH10/EX10.5b/Exa_10_5b.sce
@@ -0,0 +1,32 @@
+//Fir high pass filter design by frequency sampling
+z=%z;
+N=10;
+magHk=[0 0 0 1 1 1 1 1 0 0];
+k=[0:5 -4:-1:-1];
+fik=(-%pi*k'*(N-1)/N)+(0.5*%pi);
+for i=1:length(fik)
+    H1k(i)=magHk(i)*exp(%i*fik(i));
+end
+H1n=(dft(H1k,1));
+H2k=H1k;
+H2k(3)=0.5*%e^(-%i*1.3*%pi);
+H2k(9)=0.5*%e^(%i*1.3*%pi);
+H2n=(dft(H2k,1));
+H1Z=0;H2Z=0;
+for i=1:length(H1n)
+    H1Z=H1Z+H1n(i)*z^(-i); 
+end
+for i=1:length(H2n)
+    H2Z=H2Z+H2n(i)*z^(-i); 
+end
+F=0:0.01:1;
+F1=0:0.1:0.9;
+H1F=abs(horner(H1Z,exp(%i*2*%pi*F')));
+H2F=abs(horner(H2Z,exp(%i*2*%pi*F')));
+a=gca();
+plot2d(F1,magHk);
+plot2d(F,H2F);
+plot2d(F,H1F);
+xlabel('Digital Frequency F');
+ylabel('magnitude');
+xtitle('Low pass filter using frequency sampling');
+\ No newline at end of file
diff --git a/40/CH10/EX10.6a/Exa_10_6a.jpg b/40/CH10/EX10.6a/Exa_10_6a.jpg
new file mode 100755
index 000000000..fe1092114
--- /dev/null
+++ b/40/CH10/EX10.6a/Exa_10_6a.jpg
diff --git a/40/CH10/EX10.6a/Exa_10_6a.sce b/40/CH10/EX10.6a/Exa_10_6a.sce
new file mode 100755
index 000000000..99569f9c5
--- /dev/null
+++ b/40/CH10/EX10.6a/Exa_10_6a.sce
@@ -0,0 +1,18 @@
+//optimal Fir band stop filter design
+fp1=1;fp2=4;fs1=2;fs2=3;
+Ap=1;As=50;S=10;
+Fp1=fp1/S;Fp2=fp2/S;Fs1=fs1/S;Fs2=fs2/S;
+FT=0.1;FC=0.25
+//calculation of filter length
+delp=(10^(Ap/20)-1)/(10^(Ap/20)+1);
+dels=10^(-As/20);
+N=1+((-10*log10(delp*dels)-13)/(14.6*FT))
+N1=21;
+[hn]=eqfir(N1,[0 0.1;0.2 0.3;0.4 0.5],[1 0 1],[1 1 1]);
+[HF,fr]=frmag(hn,512);
+Hf=20*log10(HF);
+a=gca();
+plot(fr,Hf);
+xlabel('Digital frequency F');
+ylabel('Magnitude in dB');
+xtitle('optimal BSF:N=21;Ap=0.2225;As=56.79dB');
+\ No newline at end of file
diff --git a/40/CH10/EX10.6b/Exa_10_6b.jpg b/40/CH10/EX10.6b/Exa_10_6b.jpg
new file mode 100755
index 000000000..d10c7d85b
--- /dev/null
+++ b/40/CH10/EX10.6b/Exa_10_6b.jpg
diff --git a/40/CH10/EX10.6b/Exa_10_6b.sce b/40/CH10/EX10.6b/Exa_10_6b.sce
new file mode 100755
index 000000000..92dabe3e5
--- /dev/null
+++ b/40/CH10/EX10.6b/Exa_10_6b.sce
@@ -0,0 +1,19 @@
+//optimal Fir band pass filter design
+fp=8;fs=16;
+Ap=1;As=50;S=48;
+Fp=fp/S;Fs=fs/S;
+FT=0.1;FC=0.25
+//calculation of filter length
+delp=(10^(Ap/20)-1)/(10^(Ap/20)+1);
+dels=10^(-As/20);
+del=min(delp,dels);
+N=1+((-10*log10(del*del)-13)/(14.6*FT));
+N1=19;
+[hn]=eqfir(N1,[0 1/6;1/3 0.5],[1 0],[1 1]);
+[HF,fr]=frmag(hn,200);
+Hf=20*log10(HF);
+a=gca();
+plot(fr,Hf);
+xlabel('Digital frequency F');
+ylabel('Magnitude in dB');
+xtitle('optimal Half band LPF N=17');
+\ No newline at end of file
diff --git a/40/CH10/EX10.7/Exa_10_7.sce b/40/CH10/EX10.7/Exa_10_7.sce
new file mode 100755
index 000000000..029ab5aca
--- /dev/null
+++ b/40/CH10/EX10.7/Exa_10_7.sce
@@ -0,0 +1,45 @@
+//The concept of multistage Interpolation
+//(a)Single stage interpolator
+Sin=4;Sout=48;
+fp=1.8;
+fs=Sin-fp;
+FT=(fs-fp)/Sout;
+disp('By using single stage the total filter length is:')  
+L=4/FT
+//(b)Two-stage interpolator
+Sin=[4 12];
+I=[3 4];//interpolating factors
+Sout=[12 48];
+fp=[1.8 1.8];
+fs=Sin-fp;
+L1=4*Sout./(fs-fp);
+L=0;
+for i=1:length(L1)
+    L=L+L1(i);
+end
+disp('By using 2 stage interpolator filter length is:")
+ceil(L)
+//(c)3 stage interpolator with I1=2;I2=3;I3=2
+Sin=[4 8 24];
+I=[2 3 2];
+Sout=[8 24 48];
+fp=[1.8 1.8 1.8];
+fs=Sin-fp;
+L2=4*Sout./(fs-fp);L=0;
+for i=1:length(L2)
+    L=L+L2(i);
+end
+disp('By using 3 stage interpolator filter length is:")
+ceil(L)
+//(d)3 stage interpolator with I1=2;I2=3;I3=2
+Sin=[4 12 24];
+I=[3 2 2];
+Sout=[12 24 48];
+fp=[1.8 1.8 1.8];
+fs=Sin-fp;
+L3=4*Sout./(fs-fp);L=0;
+for i=1:length(L3)
+    L=L+L3(i);
+end
+disp('By using 2 stage interpolator filter length is:")
+ceil(L)
diff --git a/40/CH10/EX10.8/Exa_10_8.sce b/40/CH10/EX10.8/Exa_10_8.sce
new file mode 100755
index 000000000..994cbe31f
--- /dev/null
+++ b/40/CH10/EX10.8/Exa_10_8.sce
@@ -0,0 +1,27 @@
+//Design of interpolating filters
+//(a)Design using a single stage interpolator
+fp=1.8;Sout=48;Sin=4;
+Ap=0.6;As=50;
+fs=Sin-fp;
+//finding ripple parameters
+delp=(10^(Ap/20)-1)/(10^(Ap/20)+1);
+dels=10^(-As/20);
+N=Sout*(-10*log10(delp*dels)-13)/(14.6*(fs-fp))+1;
+disp('By using single stage interpolator the filter design is:');
+ceil(N)
+//Design using 3-stage interpolator with I1=2;I2=3;I3=2
+Ap=0.2;
+Sin=[4 8 24];
+Sout=[8 24 48];
+fp=[1.8 1.8 1.8];
+fs=Sin-fp;
+delp=(10^(Ap/20)-1)/(10^(Ap/20)+1);
+dels=10^(-As/20);
+p=14.6*(fs-fp);
+N1=((-10*log10(delp*dels)-13)./p);
+N1=(Sout.*N1)+1;N=0;
+for i=1:length(N1)
+    N=N+N1(i);
+end
+disp('By using single stage interpolator the filter design is:');
+ceil(N)
+\ No newline at end of file
diff --git a/40/CH10/EX10.9/Exa_10_9.sce b/40/CH10/EX10.9/Exa_10_9.sce
new file mode 100755
index 000000000..f31f4d205
--- /dev/null
+++ b/40/CH10/EX10.9/Exa_10_9.sce
@@ -0,0 +1,45 @@
+//The concept of multistage Decimation
+//(a)Single stage decimator
+Sin=48;Sout=4;
+fp=1.8;
+fs=Sout-fp;
+FT=(fs-fp)/Sin;
+disp('By using single stage the total filter length is:')  
+L=4/FT
+//(b)Two-stage decimator
+Sin=[48 12];
+D=[4 3];//decimating factors
+Sout=[12 4];
+fp=[1.8 1.8];
+fs=Sout-fp;
+L1=4*Sin./(fs-fp);
+L=0;
+for i=1:length(L1)
+    L=L+L1(i);
+end
+disp('By using 2 stage decimator filter length is:")
+ceil(L)
+//3 stage decimator with D1=2;D2=3;D3=2
+Sin=[48 24 8];
+D=[2 3 2];
+Sout=[24 8 4];
+fp=[1.8 1.8 1.8];
+fs=Sout-fp;
+L2=4*Sin./(fs-fp);L=0;
+for i=1:length(L2)
+    L=L+L2(i);
+end
+disp('By using 3 stage decimator filter length is:")
+ceil(L)
+//3 stage decimator with I1=2;I2=3;I3=2
+Sin=[48 24 12];
+D=[2 2 3];
+Sout=[24 12 4];
+fp=[1.8 1.8 1.8];
+fs=Sout-fp;
+L3=4*Sin./(fs-fp);L=0;
+for i=1:length(L3)
+    L=L+L3(i);
+end
+disp('By using 3 stage decimator filter length is:")
+ceil(L)
diff --git a/40/CH2/EX2.1a/Exa_2_1a.sce b/40/CH2/EX2.1a/Exa_2_1a.sce
new file mode 100755
index 000000000..14ff9d676
--- /dev/null
+++ b/40/CH2/EX2.1a/Exa_2_1a.sce
@@ -0,0 +1,11 @@
+//example 2.1.a,pg no.11
+for i=1:1:50
+    x(1,i)=3*(0.5)^(i-1);
+end
+//summation of x
+E=0
+for i=1:1:50
+    E=E+x(1,i)^2;
+end
+disp("the energy of given signal is")
+E
+\ No newline at end of file
diff --git a/40/CH2/EX2.1b/Exa_2_1b.sce b/40/CH2/EX2.1b/Exa_2_1b.sce
new file mode 100755
index 000000000..96645efef
--- /dev/null
+++ b/40/CH2/EX2.1b/Exa_2_1b.sce
@@ -0,0 +1,11 @@
+//example 2.1b,pg.no.11
+n=1:1:10;
+xn=6*cos((2*%pi*n')/4);
+a=4;
+p=0;
+for i=1:1:a
+    p=p+abs(xn(i)^2);
+end
+P=p/a;
+disp("The average power of given signal is")
+P
+\ No newline at end of file
diff --git a/40/CH2/EX2.1c/Exa_2_1c.sce b/40/CH2/EX2.1c/Exa_2_1c.sce
new file mode 100755
index 000000000..cd53703d4
--- /dev/null
+++ b/40/CH2/EX2.1c/Exa_2_1c.sce
@@ -0,0 +1,11 @@
+//example 2.1c,pg.no.11
+n=1:4;
+xn=6*%e^((%i*%pi*n')/2);
+a=4;
+p=0;
+for i=1:1:a
+    p=p+abs(xn(i)^2);
+end
+P=p/a;
+disp("The average power of given signal is")
+P
+\ No newline at end of file
diff --git a/40/CH2/EX2.2/Exa_2_2.jpg b/40/CH2/EX2.2/Exa_2_2.jpg
new file mode 100755
index 000000000..5ecf0372f
--- /dev/null
+++ b/40/CH2/EX2.2/Exa_2_2.jpg
diff --git a/40/CH2/EX2.2/Exa_2_2.sce b/40/CH2/EX2.2/Exa_2_2.sce
new file mode 100755
index 000000000..129b84ad4
--- /dev/null
+++ b/40/CH2/EX2.2/Exa_2_2.sce
@@ -0,0 +1,32 @@
+//example 2.2,pg no.12
+x=[0 2 3 4 5 6 7];
+n1=-3:1:3;
+y=x;
+n2=0:1:6;
+f=x;
+n3=-5:1:1;
+g=x(length(x):-1:1);
+n4=-3:1:3;
+h=x(length(x):-1:1);
+n5=-2:1:4;
+s=x(length(x):-1:1);
+n6=-5:1:1;
+a=gca();
+subplot(231);
+plot2d3('gnn',n1,x);
+ylabel('x[n]');
+subplot(232);
+plot2d3('gnn',n2,y);
+ylabel('y[n]=x[n-3]');
+subplot(233);
+plot2d3('gnn',n3,f);
+ylabel('f[n]=x[n+2]');
+subplot(234);
+plot2d3('gnn',n4,g);
+ylabel('g[n]=x[-n]');
+subplot(235);
+plot2d3('gnn',n5,h);
+ylabel('h[n]=x[-n+1]');
+subplot(236);
+plot2d3('gnn',n6,s);
+ylabel('s[n]=x[-n-2]');
diff --git a/40/CH2/EX2.3a/Exa_2_3a.sce b/40/CH2/EX2.3a/Exa_2_3a.sce
new file mode 100755
index 000000000..1cf640075
--- /dev/null
+++ b/40/CH2/EX2.3a/Exa_2_3a.sce
@@ -0,0 +1,21 @@
+//example 2.3a pg.no.14
+clear;clc;close;
+n=-2:2;
+x1=[4 -2 4 -6 0];
+x2=0.5*x1//x[n]
+x3=0.5*[x1(length(x1):-1:1)];//x[-n]
+xe=(x2+x3);//even part
+xo=(x2-x3);//odd part
+a=gca();
+a.thickness=2;
+a.x_location="middle";
+a.y_location="middle";
+plot2d3('gnn',n,xe,rect=[-4 -6 4 6])
+xtitle('graphical representation of even part of x[n]','n','x[n]')
+xset('window',1)
+b=gca();
+b.thickness=2;
+b.y_location="middle";
+b.x_location="middle";
+plot2d3('gnn',n,xo,rect=[-2 -4 2 4])
+xtitle('graphical representation of odd part of x[n]','n','x[n]')
diff --git a/40/CH2/EX2.3a/Exa_2_3a_0.jpg b/40/CH2/EX2.3a/Exa_2_3a_0.jpg
new file mode 100755
index 000000000..d4cfc3947
--- /dev/null
+++ b/40/CH2/EX2.3a/Exa_2_3a_0.jpg
diff --git a/40/CH2/EX2.3a/Exa_2_3a_1.jpg b/40/CH2/EX2.3a/Exa_2_3a_1.jpg
new file mode 100755
index 000000000..9af674607
--- /dev/null
+++ b/40/CH2/EX2.3a/Exa_2_3a_1.jpg
diff --git a/40/CH2/EX2.3b/Exa_2_3b.sce b/40/CH2/EX2.3b/Exa_2_3b.sce
new file mode 100755
index 000000000..ec3e8ba9b
--- /dev/null
+++ b/40/CH2/EX2.3b/Exa_2_3b.sce
@@ -0,0 +1,21 @@
+//example 2.3a pg.no.14
+clear;clc;close;
+x1=[0 0 0 0 0 1 1 1 1 ];
+n=-4:4;
+x2=0.5*x1//x[n]
+x3=0.5*[x1(length(x1):-1:1)]//x[-n]
+xe=(x2+x3);//even part
+xo=(x2-x3);//odd part
+a=gca();
+a.thickness=2;
+a.y_location="middle";
+a.x_location="middle";
+plot2d3('gnn',n,xe,rect=[-4 -1 4 1]);
+xtitle('graphical representation of even part of x[n]','n','x[n]')
+xset('window',1)
+b=gca();
+b.thickness=2;
+b.y_location="middle";
+b.x_location="middle";
+plot2d3('gnn',n,xo,rect=[-4 -1 4 1]);
+xtitle('graphical representation of odd part of x[n]','n','x[n]')
diff --git a/40/CH2/EX2.3b/Exa_2_3b_0.jpg b/40/CH2/EX2.3b/Exa_2_3b_0.jpg
new file mode 100755
index 000000000..a6b27c9e2
--- /dev/null
+++ b/40/CH2/EX2.3b/Exa_2_3b_0.jpg
diff --git a/40/CH2/EX2.3b/Exa_2_3b_1.jpg b/40/CH2/EX2.3b/Exa_2_3b_1.jpg
new file mode 100755
index 000000000..bb76d1e7b
--- /dev/null
+++ b/40/CH2/EX2.3b/Exa_2_3b_1.jpg
diff --git a/40/CH2/EX2.4a/Exa_2_4a.sce b/40/CH2/EX2.4a/Exa_2_4a.sce
new file mode 100755
index 000000000..36af8b99c
--- /dev/null
+++ b/40/CH2/EX2.4a/Exa_2_4a.sce
@@ -0,0 +1,12 @@
+//example 2.4a pg.no.17
+x=[1 2 5 -1];
+xm=2;//denotes 2nd sample has pad.
+y=[x(1:2:xm-2),x(xm:2:length(x))]//decimation
+h=[x(1:1/3:length(x))]//step interpolated
+g=h;
+for i=2:3
+    g(i:3:length(g))=0;
+end
+//zero interpolated
+x1=1:3:3*length(x);
+s=interpln([x1;x],1:10)//linear interpolated
+\ No newline at end of file
diff --git a/40/CH2/EX2.4b/Exa_2_4b.sce b/40/CH2/EX2.4b/Exa_2_4b.sce
new file mode 100755
index 000000000..bb5d5dba1
--- /dev/null
+++ b/40/CH2/EX2.4b/Exa_2_4b.sce
@@ -0,0 +1,7 @@
+//example 2.4 b,c.pg.no.17
+x=[3 4 5 6];
+xm=3;//denotes 3rd sample has pad
+xm=xm-1;//shifting
+g=[x(xm-2:-2:1),x(xm:2:length(x))]//decimation
+xm=3;
+h=[x(1:1/2:length(x))]//step interpolated
diff --git a/40/CH2/EX2.4c/Exa_2_4c.sce b/40/CH2/EX2.4c/Exa_2_4c.sce
new file mode 100755
index 000000000..ecda14aa3
--- /dev/null
+++ b/40/CH2/EX2.4c/Exa_2_4c.sce
@@ -0,0 +1,9 @@
+//example 2.4c,pg.no.17
+x=[3 4 5 6];
+xm=3;
+xm=xm+1*(xm-1);//shift in pad due to interpolation
+xm=xm-2//normal shifting
+x1=[x(1:1/3:length(x))]//step interpolated
+xm=3;
+xm=xm+2*(xm-1)//shift in pad due to interpolation
+y=[x1(1:2:xm-2),x1(xm:2:length(x1))]//decimation
+\ No newline at end of file
diff --git a/40/CH2/EX2.4d/Exa_2_4d.sce b/40/CH2/EX2.4d/Exa_2_4d.sce
new file mode 100755
index 000000000..43283683c
--- /dev/null
+++ b/40/CH2/EX2.4d/Exa_2_4d.sce
@@ -0,0 +1,8 @@
+//example 2.4d,pg.no.17
+x=[2 4 6 8]
+xm=3;//denote 3rd sample has pad
+x1=[1 3 5 7]
+x2=interpln([x1;x],1:6)
+xm=xm+1*(xm-1);//shift in pad due to interpolation
+xm=xm-1//shift in pad due to delay
+y=[x2(2:2:xm-2),x2(xm:2:length(x2))]//decimation
+\ No newline at end of file
diff --git a/40/CH2/EX2.5/Exa_2_5.sce b/40/CH2/EX2.5/Exa_2_5.sce
new file mode 100755
index 000000000..1b7a6da59
--- /dev/null
+++ b/40/CH2/EX2.5/Exa_2_5.sce
@@ -0,0 +1,9 @@
+//example 2.5,pg.no.20
+x=[1 2 4 8 16 32 64];
+y=[0 0 0 1 0 0 0];
+z=x.*y;
+a=0;
+for i=1:length(z)
+    a=a+z(i);
+end
+z,a//a=summation of z
+\ No newline at end of file
diff --git a/40/CH2/EX2.6/Exa_2_6.sci b/40/CH2/EX2.6/Exa_2_6.sci
new file mode 100755
index 000000000..99ebfe922
--- /dev/null
+++ b/40/CH2/EX2.6/Exa_2_6.sci
@@ -0,0 +1,31 @@
+//example 2.6 pg.no.23
+function[p]=period(x)
+for i=2:length(x)
+    v=i
+    if (abs(x(i)-x(1))<0.00001)    
+        k=2
+        for j=i+1:i+i
+            if (abs(x(j)-x(k))<0.00001)   
+                v=v+1
+            end
+        k=k+1;      
+        end
+     end 
+    if (v==(2*i)) then
+        break
+    end
+end
+p=i-1
+endfunction
+for i=1:60
+    x1(i)=cos((2*%pi*8*i)/25);
+end
+for i=1:60
+    x2(i)=exp(%i*0.2*i*%pi)+exp(-%i*0.3*i*%pi);
+end
+for i=1:45
+    x3(i)=2*cos((40*%pi*i)/75)+sin((60*%pi*i)/75);
+end
+period(x1)
+period(x2)
+period(x3)
+\ No newline at end of file
diff --git a/40/CH2/EX2.7/Exa_2_7.sce b/40/CH2/EX2.7/Exa_2_7.sce
new file mode 100755
index 000000000..0e4a73afd
--- /dev/null
+++ b/40/CH2/EX2.7/Exa_2_7.sce
@@ -0,0 +1,14 @@
+//example 2.7.pg.no.27
+f=100;
+s=240;
+s1=s;
+aliasfrequency(f,s)
+s=140;
+s1=s;
+aliasfrequency(f,s,s1)
+s=90;
+s1=s;
+aliasfrequency(f,s,s1)
+s=35;
+s1=s;
+aliasfrequency(f,s,s1)
diff --git a/40/CH2/EX2.8/Exa_2_8.sce b/40/CH2/EX2.8/Exa_2_8.sce
new file mode 100755
index 000000000..f9ac5da10
--- /dev/null
+++ b/40/CH2/EX2.8/Exa_2_8.sce
@@ -0,0 +1,6 @@
+f=100;
+s=210;
+s1=420;
+aliasfrequency(f,s,s1)
+s=140;
+aliasfrequency(f,s,s1)
+\ No newline at end of file
diff --git a/40/CH3/EX3.19a/Exa_3_19a.sce b/40/CH3/EX3.19a/Exa_3_19a.sce
new file mode 100755
index 000000000..4d9b343a4
--- /dev/null
+++ b/40/CH3/EX3.19a/Exa_3_19a.sce
@@ -0,0 +1,24 @@
+//Analytical evaluation of Discrete Convolution
+clear;close;clc;
+max_limit=10;
+h=ones(1,max_limit);
+n2=0:length(h)-1;
+x=h;
+n1=-length(x)+1:0;
+y=convol(x,h);
+n=-length(x)+1:length(h)-1;
+a=gca();
+subplot(211);
+plot2d3('gnn',n2,h)
+xtitle('impulse Response','n','h[n]');
+a.thickness=2;
+a.y_location="origin";
+subplot(212);
+plot2d3('gnn',n1,x)
+a.y_location="origin";
+xtitle('input response','n','x[n]');
+xset("window",1);
+a=gca();
+plot2d3('gnn',n,y)
+xtitle('output response','n','y[n]');
+
diff --git a/40/CH3/EX3.19a/Exa_3_19a_0.jpg b/40/CH3/EX3.19a/Exa_3_19a_0.jpg
new file mode 100755
index 000000000..f596017dc
--- /dev/null
+++ b/40/CH3/EX3.19a/Exa_3_19a_0.jpg
diff --git a/40/CH3/EX3.19a/Exa_3_19a_1.jpg b/40/CH3/EX3.19a/Exa_3_19a_1.jpg
new file mode 100755
index 000000000..dd79cb972
--- /dev/null
+++ b/40/CH3/EX3.19a/Exa_3_19a_1.jpg
diff --git a/40/CH3/EX3.19b/Exa_3_19b.sce b/40/CH3/EX3.19b/Exa_3_19b.sce
new file mode 100755
index 000000000..8826c7283
--- /dev/null
+++ b/40/CH3/EX3.19b/Exa_3_19b.sce
@@ -0,0 +1,26 @@
+clear;close;clc;
+max_limit=10;
+for n=1:max_limit
+    h(n)=(0.4)^n;
+end
+n2=0:length(h)-1;
+for n=1:max_limit
+    x(n)=(0.8)^n;
+end
+n1=-length(x)+1:0;
+y=convol(x,h)
+n=-length(x)+1:length(h)-1;
+a=gca();
+subplot(211);
+plot2d3('gnn',n2,h)
+xtitle('impulse Response','n','h[n]');
+a.thickness=2;
+a.y_location="origin";
+subplot(212);
+plot2d3('gnn',n1,x)
+a.y_location="origin";
+xtitle('input response','n','x[n]');
+xset("window",1);
+a=gca();
+plot2d3('gnn',n,y)
+xtitle('output response','n','y[n]');
diff --git a/40/CH3/EX3.19b/Exa_3_19b_0.jpg b/40/CH3/EX3.19b/Exa_3_19b_0.jpg
new file mode 100755
index 000000000..58f41cf8f
--- /dev/null
+++ b/40/CH3/EX3.19b/Exa_3_19b_0.jpg
diff --git a/40/CH3/EX3.19b/Exa_3_19b_1.jpg b/40/CH3/EX3.19b/Exa_3_19b_1.jpg
new file mode 100755
index 000000000..378fff963
--- /dev/null
+++ b/40/CH3/EX3.19b/Exa_3_19b_1.jpg
diff --git a/40/CH3/EX3.19c/Exa_3_19c.sce b/40/CH3/EX3.19c/Exa_3_19c.sce
new file mode 100755
index 000000000..0a7d32a0b
--- /dev/null
+++ b/40/CH3/EX3.19c/Exa_3_19c.sce
@@ -0,0 +1,29 @@
+//Analytical Evaluation of Discrete convolution
+clear;close;clc;
+max_limit=5;
+h(1)=0;
+for n=2:max_limit
+    h(n)=0.8^n;
+end
+n2=0:length(h)-1;
+x=[0 ones(1:max_limit)]
+n1=-length(x)+1:0;
+y=convol(x,h);
+n=-length(x)+1:length(h)-1;
+a=gca();
+subplot(211);
+plot2d3('gnn',n2,h)
+xtitle('impulse Response','n','h[n]');
+a.thickness=2;
+a.y_location="origin";
+a=gca();
+subplot(212);
+plot2d3('gnn',n1,x)
+a.y_location="origin";
+xtitle('input response','n','x[n]');
+xset("window",1);
+a=gca();
+plot2d3('gnn',n,y)
+a.y_location="origin";
+a.x_location="origin";
+xtitle('output response','n','y[n]');
diff --git a/40/CH3/EX3.19c/Exa_3_19c_0.jpg b/40/CH3/EX3.19c/Exa_3_19c_0.jpg
new file mode 100755
index 000000000..be71ab970
--- /dev/null
+++ b/40/CH3/EX3.19c/Exa_3_19c_0.jpg
diff --git a/40/CH3/EX3.19c/Exa_3_19c_1.jpg b/40/CH3/EX3.19c/Exa_3_19c_1.jpg
new file mode 100755
index 000000000..27785d94f
--- /dev/null
+++ b/40/CH3/EX3.19c/Exa_3_19c_1.jpg
diff --git a/40/CH3/EX3.20a/Exa_3_20_a.sce b/40/CH3/EX3.20a/Exa_3_20_a.sce
new file mode 100755
index 000000000..1012ceb5c
--- /dev/null
+++ b/40/CH3/EX3.20a/Exa_3_20_a.sce
@@ -0,0 +1,6 @@
+//properties of convolution
+x=[1 2 3 4 5];
+h=[1 zeros(1:5)];
+a=convol(x,h);
+b=convol(h,x);
+a==b
diff --git a/40/CH3/EX3.20b/Exa_3_20_b.sce b/40/CH3/EX3.20b/Exa_3_20_b.sce
new file mode 100755
index 000000000..2b03d5df8
--- /dev/null
+++ b/40/CH3/EX3.20b/Exa_3_20_b.sce
@@ -0,0 +1,9 @@
+//Convolution with Step Function
+x=[1 2 3 4 5];
+h=[ones(1:5)];
+a=convol(h,x);
+b(1)=a(1);
+for i=2:length(x)
+    b(i)=b(i-1)+x(i);
+end
+disp(a(1:length(x)),b,'Step Response is running sum of impulses can be seen below');
diff --git a/40/CH3/EX3.21a/Exa_3_21a.sce b/40/CH3/EX3.21a/Exa_3_21a.sce
new file mode 100755
index 000000000..ec568ae53
--- /dev/null
+++ b/40/CH3/EX3.21a/Exa_3_21a.sce
@@ -0,0 +1,27 @@
+//convolution of finite length signals
+clear;close;clc;
+max_limit=10;
+h=[1 2 2 3];
+n2=0:length(h)-1;
+x=[2 -1 3];
+n1=0:length(x)-1;
+y=convol(x,h);
+n=0:length(h)+length(x)-2;
+a=gca();
+subplot(211);
+plot2d3('gnn',n2,h)
+xtitle('impulse Response','n','h[n]');
+a.thickness=2;
+a.y_location="origin";
+a=gca();
+subplot(212);
+plot2d3('gnn',n1,x)
+a.y_location="origin";
+a.x_location="origin";
+xtitle('input response','n','x[n]');
+xset("window",2);
+a=gca();
+plot2d3('gnn',n,y)
+a.y_location="origin";
+xtitle('output response','n','y[n]');
+
diff --git a/40/CH3/EX3.21a/Exa_3_21a_0.jpg b/40/CH3/EX3.21a/Exa_3_21a_0.jpg
new file mode 100755
index 000000000..bcbe3680f
--- /dev/null
+++ b/40/CH3/EX3.21a/Exa_3_21a_0.jpg
diff --git a/40/CH3/EX3.21a/Exa_3_21a_1.jpg b/40/CH3/EX3.21a/Exa_3_21a_1.jpg
new file mode 100755
index 000000000..06bc18ad1
--- /dev/null
+++ b/40/CH3/EX3.21a/Exa_3_21a_1.jpg
diff --git a/40/CH3/EX3.21b/Exa_3_21b.sce b/40/CH3/EX3.21b/Exa_3_21b.sce
new file mode 100755
index 000000000..428a164d7
--- /dev/null
+++ b/40/CH3/EX3.21b/Exa_3_21b.sce
@@ -0,0 +1,25 @@
+clear;close;clc;
+max_limit=10;
+h=[2 5 0 4];
+n2=-2:length(h)-3;
+x=[4 1 3];
+n1=-1:length(x)-2;
+y=convol(x,h);
+n=-3:length(x)+length(h)-5;
+a=gca();
+subplot(211);
+plot2d3('gnn',n2,h)
+xtitle('impulse Response','n','h[n]');
+a.thickness=2;
+a.y_location="origin";
+a=gca();
+subplot(212);
+plot2d3('gnn',n1,x)
+a.y_location="origin";
+xtitle('input response','n','x[n]');
+xset("window",1);
+a=gca();
+plot2d3('gnn',n,y)
+a.y_location="origin";
+a.x_location="origin";
+xtitle('output response','n','y[n]');
diff --git a/40/CH3/EX3.21b/Exa_3_21b_0.jpg b/40/CH3/EX3.21b/Exa_3_21b_0.jpg
new file mode 100755
index 000000000..009f03fb9
--- /dev/null
+++ b/40/CH3/EX3.21b/Exa_3_21b_0.jpg
diff --git a/40/CH3/EX3.21b/Exa_3_21b_1.jpg b/40/CH3/EX3.21b/Exa_3_21b_1.jpg
new file mode 100755
index 000000000..6d43346c5
--- /dev/null
+++ b/40/CH3/EX3.21b/Exa_3_21b_1.jpg
diff --git a/40/CH3/EX3.21c/Exa_3_21c.sce b/40/CH3/EX3.21c/Exa_3_21c.sce
new file mode 100755
index 000000000..a7bc600df
--- /dev/null
+++ b/40/CH3/EX3.21c/Exa_3_21c.sce
@@ -0,0 +1,25 @@
+clear;close;clc;
+max_limit=10;
+h=[1/2 1/2 1/2];
+n2=0:length(h)-1;
+x=[2 4 6 8 10];
+n1=0:length(x)-1;
+y=convol(x,h);
+n=0:length(x)+length(h)-2;
+a=gca();
+subplot(211);
+plot2d3('gnn',n2,h);
+xtitle('impulse Response','n','h[n]');
+a.thickness=2;
+a.y_location="origin";
+a=gca();
+subplot(212);
+plot2d3('gnn',n1,x);
+a.y_location="origin";
+xtitle('input response','n','x[n]');
+xset("window",1);
+a=gca();
+plot2d3('gnn',n,y)
+a.y_location="origin";
+a.x_location="origin";
+xtitle('output response','n','y[n]');
diff --git a/40/CH3/EX3.21c/Exa_3_21c_0.jpg b/40/CH3/EX3.21c/Exa_3_21c_0.jpg
new file mode 100755
index 000000000..e9f503e59
--- /dev/null
+++ b/40/CH3/EX3.21c/Exa_3_21c_0.jpg
diff --git a/40/CH3/EX3.21c/Exa_3_21c_1.jpg b/40/CH3/EX3.21c/Exa_3_21c_1.jpg
new file mode 100755
index 000000000..639a33fb2
--- /dev/null
+++ b/40/CH3/EX3.21c/Exa_3_21c_1.jpg
diff --git a/40/CH3/EX3.22/Exa_3_22.sce b/40/CH3/EX3.22/Exa_3_22.sce
new file mode 100755
index 000000000..958ae815f
--- /dev/null
+++ b/40/CH3/EX3.22/Exa_3_22.sce
@@ -0,0 +1,25 @@
+max_limit=10;
+h=[2 5 0 4];
+n2=0:length(h)-1;
+x=[4 1 3];
+n1=0:length(x)-1;
+y=convol(x,h);
+n=0:length(x)+length(h)-2;
+a=gca();
+subplot(211);
+plot2d3('gnn',n2,h)
+xtitle('impulse Response','n','h[n]');
+a.thickness=2;
+a.y_location="origin";
+a=gca();
+subplot(212);
+plot2d3('gnn',n1,x)
+a.y_location="origin";
+a.x_location="origin";
+xtitle('input response','n','x[n]');
+xset("window",1);
+a=gca();
+plot2d3('gnn',n,y)
+a.y_location="origin";
+a.x_location="origin";
+xtitle('output response','n','y[n]');
diff --git a/40/CH3/EX3.22/Exa_3_22_0.jpg b/40/CH3/EX3.22/Exa_3_22_0.jpg
new file mode 100755
index 000000000..e347a880f
--- /dev/null
+++ b/40/CH3/EX3.22/Exa_3_22_0.jpg
diff --git a/40/CH3/EX3.22/Exa_3_22_1.jpg b/40/CH3/EX3.22/Exa_3_22_1.jpg
new file mode 100755
index 000000000..39f2f95cc
--- /dev/null
+++ b/40/CH3/EX3.22/Exa_3_22_1.jpg
diff --git a/40/CH3/EX3.23/Exa_3_23.sce b/40/CH3/EX3.23/Exa_3_23.sce
new file mode 100755
index 000000000..3ad727958
--- /dev/null
+++ b/40/CH3/EX3.23/Exa_3_23.sce
@@ -0,0 +1,17 @@
+//convolution by polynomial method
+x=[4 1 3];
+h=[2 5 0 4];
+z=%z;
+n=length(x)-1:-1:0;
+X=x*z^n';
+n1=length(h)-1:-1:0;
+H=h*z^n1';
+y=X*H
+//effect of zero insertion on convolution
+h=[2 0 5 0 0 0 4];
+x=[4 0 1 0 3];
+y=convol(x,h)
+//effect of zero padding on convolution
+h=[2 5 0 4 0 0];
+x=[4 1 3 0];
+y=convol(x,h)
+\ No newline at end of file
diff --git a/40/CH3/EX3.25/Exa_3_25.sce b/40/CH3/EX3.25/Exa_3_25.sce
new file mode 100755
index 000000000..abe567eac
--- /dev/null
+++ b/40/CH3/EX3.25/Exa_3_25.sce
@@ -0,0 +1,24 @@
+//concepts based on stability and Causality
+function[]=stability(X)
+if (abs(roots(X))<1)
+    disp("given system is stable")
+else 
+    disp("given system is not stable")
+end
+endfunction
+x=[1 -1/6 -1/6];
+z=%z;
+n=length(x)-1:-1:0;
+//characteristic eqn is
+X=x*(z)^n'
+stability(X)
+x=[1 -1];
+n=length(x)-1:-1:0;
+//characteristic eqn is
+X=x*(z)^n'
+stability(X)
+x=[1 -2 1];
+n=length(x)-1:-1:0;
+//characteristic eqn is
+X=x*(z)^n'
+stability(X)
diff --git a/40/CH3/EX3.26/Exa_3_26.sci b/40/CH3/EX3.26/Exa_3_26.sci
new file mode 100755
index 000000000..039b1b19f
--- /dev/null
+++ b/40/CH3/EX3.26/Exa_3_26.sci
@@ -0,0 +1,27 @@
+//Response of periodic inputs
+function[p]=period(x)
+for i=2:length(x)
+    v=i
+    if (abs(x(i)-x(1))<0.00001)    
+        k=2
+        for j=i+1:i+i
+            if (abs(x(j)-x(k))<0.00001)   
+                v=v+1
+            end
+        k=k+1;      
+        end
+     end 
+    if (v==(2*i)) then
+        break
+    end
+end
+p=i-1
+endfunction
+x=[1 2 -3 1 2 -3 1 2 -3];
+h=[1 1];
+y=convol(x,h)
+y(1)=y(4);
+period(x)
+period(y)
+h=[1 1 1];
+y=convol(x,h)
+\ No newline at end of file
diff --git a/40/CH3/EX3.27/Exa_3_27.sce b/40/CH3/EX3.27/Exa_3_27.sce
new file mode 100755
index 000000000..bfe72d463
--- /dev/null
+++ b/40/CH3/EX3.27/Exa_3_27.sce
@@ -0,0 +1,10 @@
+//to find periodic extension
+x=[1 5 2;0 4 3;6 7 0];
+y=[0 0 0];
+for i=1:3
+    for j=1:3
+        y(i)=y(i)+x(j,i);
+    end
+end
+y
+
diff --git a/40/CH3/EX3.28/Exa_3_28.sce b/40/CH3/EX3.28/Exa_3_28.sce
new file mode 100755
index 000000000..1c25af7c7
--- /dev/null
+++ b/40/CH3/EX3.28/Exa_3_28.sce
@@ -0,0 +1,25 @@
+//method of wrapping to fing convolution of periodic signal with one period
+x=[1 2 -3];
+h=[1 1];
+y1=convol(h,x)
+y1=[y1,zeros(5:9)]
+y2=[y1(1:3);y1(4:6);y1(7:9)];
+y=[0 0 0];
+for i=1:3
+    for j=1:3
+        y(i)=y(i)+y2(j,i);
+    end
+end
+y
+x=[2 1 3];
+h=[2 1 1 3 1];
+y1=convol(h,x)
+y1=[y1,zeros(8:9)]
+y2=[y1(1:3);y1(4:6);y1(7:9)];
+y=[0 0 0];
+for i=1:3
+    for j=1:3
+        y(i)=y(i)+y2(j,i);
+    end
+end
+y
+\ No newline at end of file
diff --git a/40/CH3/EX3.29/Exa_3_29.sce b/40/CH3/EX3.29/Exa_3_29.sce
new file mode 100755
index 000000000..11540e0bf
--- /dev/null
+++ b/40/CH3/EX3.29/Exa_3_29.sce
@@ -0,0 +1,13 @@
+//periodic or circular convolution
+x=[1 0 1 1];
+h=[1 2 3 1];
+y1=convol(h,x)
+y1=[y1,zeros(8:12)];
+y2=[y1(1:4);y1(5:8);y1(9:12)];
+y=[0 0 0 0];
+for i=1:4
+    for j=1:3
+        y(i)=y(i)+y2(j,i);
+    end
+end
+y
+\ No newline at end of file
diff --git a/40/CH3/EX3.30/Exa_3_30.sce b/40/CH3/EX3.30/Exa_3_30.sce
new file mode 100755
index 000000000..f322121b9
--- /dev/null
+++ b/40/CH3/EX3.30/Exa_3_30.sce
@@ -0,0 +1,9 @@
+//periodic convolution by circulant matrix
+x=[1 0 2];
+h=[1;2;3];
+//generation of circulant matrix
+c(1,:)=x;
+for i=2:length(x)
+    c(i,:)=[x(length(x):length(x)-i),x(1:length(x)-i)]
+end
+c'
+\ No newline at end of file
diff --git a/40/CH3/EX3.32/Exa_3_32.sce b/40/CH3/EX3.32/Exa_3_32.sce
new file mode 100755
index 000000000..683f225de
--- /dev/null
+++ b/40/CH3/EX3.32/Exa_3_32.sce
@@ -0,0 +1,9 @@
+//deconvolution by polynomial division
+x=[2 5 0 4];
+y=[8 22 11 31 4 12];
+z=%z
+n=length(x)-1:-1:0;
+X=x*(z)^n'
+n1=length(y)-1:-1:0;
+Y=y*(z)^n1'
+h=Y/X
+\ No newline at end of file
diff --git a/40/CH3/EX3.33/Exa_3_33.sce b/40/CH3/EX3.33/Exa_3_33.sce
new file mode 100755
index 000000000..e8e487449
--- /dev/null
+++ b/40/CH3/EX3.33/Exa_3_33.sce
@@ -0,0 +1,13 @@
+//discrete auto correlation and cross correlation
+x=[2 5 0 4];
+h=[3 1 4];
+x1=x(length(x):-1:1)
+h1=h(length(h):-1:1)
+rxhn=convol(x,h1)
+rhxn=convol(x1,h)
+rhxn1=rhxn(length(rhxn):-1:1)
+//we observe that rhxn1=rxhn
+x=[3 1 -4];
+x1=x(length(x):-1:1)
+rxxn=convol(x,x1)
+//we observe that rxxn is even symmetric about origin
diff --git a/40/CH3/EX3.35/Exa_3_35.sce b/40/CH3/EX3.35/Exa_3_35.sce
new file mode 100755
index 000000000..de305d3b7
--- /dev/null
+++ b/40/CH3/EX3.35/Exa_3_35.sce
@@ -0,0 +1,33 @@
+//discrete periodic auto correlation and cross correlation
+x=[2 5 0 4];
+h=[3 1 -1 2];
+x1=x(length(x):-1:1);
+h1=h(length(h):-1:1);
+rxhn=convol(x,h1)
+rhxn=convol(x1,h)
+rxxn=convol(x,x1)
+rhhn=convol(h,h1)
+y1=[rxhn,zeros(8:12)];
+y2=[y1(1:4);y1(5:8);y1(9:12)];
+y3=[rhxn,zeros(8:12)];
+y4=[y3(1:4);y3(5:8);y3(9:12)];
+y5=[rxxn,zeros(8:12)];
+y6=[y5(1:4);y5(5:8);y5(9:12)];
+y7=[rhhn,zeros(8:12)];
+y8=[y7(1:4);y7(5:8);y7(9:12)];
+rxhp=[0 0 0 0];
+rhxp=[0 0 0 0];
+rxxn=[0 0 0 0];
+rhhp=[0 0 0 0];
+for i=1:4
+     for j=1:3
+        rhxp(i)=rhxp(i)+y4(j,i);
+        rxhp(i)=rxhp(i)+y2(j,i);
+        rxxn(i)=rxxn(i)+y6(j,i);
+        rhhp(i)=rhhp(i)+y8(j,i);
+    end
+end
+rxhp
+rhxp
+rxxn
+rhhp
+\ No newline at end of file
diff --git a/40/CH3/EX3.5/Exa_3_5.sce b/40/CH3/EX3.5/Exa_3_5.sce
new file mode 100755
index 000000000..c64444620
--- /dev/null
+++ b/40/CH3/EX3.5/Exa_3_5.sce
@@ -0,0 +1,9 @@
+//Response of non-recursive Filters
+for i=1:4
+    x(i)=0.5^i;
+end
+x1=[0;1;x(1:2)]
+for i=1:4
+     y(i)=2*x(i)-3*x1(i);
+end     
+y(1),y(2)
+\ No newline at end of file
diff --git a/40/CH4/EX4.10/Exa_4_10.sce b/40/CH4/EX4.10/Exa_4_10.sce
new file mode 100755
index 000000000..b89aaf3b8
--- /dev/null
+++ b/40/CH4/EX4.10/Exa_4_10.sce
@@ -0,0 +1,14 @@
+//inverse transform of sequences
+//(a)X(z)=3z^-1+5z^-3+2z^-4
+z=%z;
+X1=[3*z^-1;0;5*z^-3;2*z^-4];
+n1=1:4;
+ZI=z^n1';
+x1=numer(X1.*ZI);
+disp(x1,"x[n]=");
+//(b)X(z)=2z^2-5z+5z^-1-2z^-2
+X2=[2*z^2;-5*z;0;5*z^-1;-2*z^-2];
+n2=-2:2;
+ZI=z^n2';
+x2=numer(X2.*ZI);
+disp(x2,"x[n]=");
+\ No newline at end of file
diff --git a/40/CH4/EX4.11/Exa_4_11.sce b/40/CH4/EX4.11/Exa_4_11.sce
new file mode 100755
index 000000000..e190701ff
--- /dev/null
+++ b/40/CH4/EX4.11/Exa_4_11.sce
@@ -0,0 +1,3 @@
+//inverse transform by long division
+z=%z;
+x=ldiv(z-4,1-z+z^2,5)
+\ No newline at end of file
diff --git a/40/CH4/EX4.12/Exa_4_12.sce b/40/CH4/EX4.12/Exa_4_12.sce
new file mode 100755
index 000000000..4ec3cd076
--- /dev/null
+++ b/40/CH4/EX4.12/Exa_4_12.sce
@@ -0,0 +1,11 @@
+//inverse z transforms from standard transforms
+z=%z;
+xz=z/((z-0.5)*(z-0.25));
+yz=xz/z;
+pfss(yz)
+//hence x[n]=-4(0.25)^n*un+4(0.5)^n*un;
+xz=1/((z-0.5)*(z-0.25));
+yz=xz/z;
+pfss(yz)
+//hence x[n]=-4(0.25)^n-1*u[n-1]+4(0.5)^n-1*u[n-1];
+
diff --git a/40/CH4/EX4.1b/Exa_4_1b.sci b/40/CH4/EX4.1b/Exa_4_1b.sci
new file mode 100755
index 000000000..78e129063
--- /dev/null
+++ b/40/CH4/EX4.1b/Exa_4_1b.sci
@@ -0,0 +1,7 @@
+function[za]=ztransfer(sequence,n)
+    z=poly(0,'z','r')
+    za=sequence*(1/z)^n'
+endfunction
+x1=[2 1 -5 4];
+n=-1:length(x1)-2;
+ztransfer(x1,n)    
+\ No newline at end of file
diff --git a/40/CH4/EX4.20/Exa_4_20.sce b/40/CH4/EX4.20/Exa_4_20.sce
new file mode 100755
index 000000000..d8619d9c5
--- /dev/null
+++ b/40/CH4/EX4.20/Exa_4_20.sce
@@ -0,0 +1,22 @@
+//z transform of switched periodic signals
+z=%z;
+//sol. for 4.20a
+x1=[0 1 2];
+n=0:2;
+N=3;
+x1z=x1*(1/z)^n'
+xz=x1z/(1-z^-N)
+//sol.for 4.20b
+x1=[0 1 0 -1];
+n=0:3;
+N=4;
+x1z=x1*(1/z)^n'
+xz=x1z/(1-z^-N)
+//sol.for 4.20c
+xz=(2+z^-1)/(1-z^-3);
+x1z=numer(xz)
+//thus first period of xn is [2 1 0]
+//sol.for 4.20d
+xz=(z^-1-z^-4)/(1-z^-6);
+x1z=numer(xz)
+//thus first period of xn is [0 1 0 0 -1 0]
+\ No newline at end of file
diff --git a/40/CH4/EX4.4a/Exa_4_4a.jpg b/40/CH4/EX4.4a/Exa_4_4a.jpg
new file mode 100755
index 000000000..3d2add22f
--- /dev/null
+++ b/40/CH4/EX4.4a/Exa_4_4a.jpg
diff --git a/40/CH4/EX4.4a/Exa_4_4a.sce b/40/CH4/EX4.4a/Exa_4_4a.sce
new file mode 100755
index 000000000..e8866a358
--- /dev/null
+++ b/40/CH4/EX4.4a/Exa_4_4a.sce
@@ -0,0 +1,8 @@
+//Pole-Zero plots
+z=%z;
+az=2*z*(z+1);
+bz=(z-1/3)*((z^2)+1/4)*((z^2)+4*z+5);
+poles=roots(bz)
+zeroes=roots(az)
+h=az/bz
+plzr(h)
+\ No newline at end of file
diff --git a/40/CH4/EX4.4b/Exa_4_4b.jpg b/40/CH4/EX4.4b/Exa_4_4b.jpg
new file mode 100755
index 000000000..fd0732194
--- /dev/null
+++ b/40/CH4/EX4.4b/Exa_4_4b.jpg
diff --git a/40/CH4/EX4.4b/Exa_4_4b.sce b/40/CH4/EX4.4b/Exa_4_4b.sce
new file mode 100755
index 000000000..1b6a0ec81
--- /dev/null
+++ b/40/CH4/EX4.4b/Exa_4_4b.sce
@@ -0,0 +1,8 @@
+//Pole-Zero plots
+z=%z;
+az=z^4+4.25*z^2+1;
+bz=z^4;
+poles=roots(bz)
+zeroes=roots(az)
+h=az/bz
+plzr(h)
+\ No newline at end of file
diff --git a/40/CH4/EX4.8/Exa_4_8.sce b/40/CH4/EX4.8/Exa_4_8.sce
new file mode 100755
index 000000000..b897889c0
--- /dev/null
+++ b/40/CH4/EX4.8/Exa_4_8.sce
@@ -0,0 +1,17 @@
+//stability of recursive filter
+//for roc:/z/>/a/ 
+a=input('enter the value of alpha')
+z=%z;
+H=z/(z-a);
+if (abs(a)<1)
+    disp("system is stable")
+else
+    disp("system is not stable")
+ end
+ //for roc:/z/</a/
+ if (abs(a)>1)
+    disp("system is stable")
+else
+    disp("system is not stable")
+ end
+        
+\ No newline at end of file
diff --git a/40/CH4/EX4.9/Exa_4_9.sce b/40/CH4/EX4.9/Exa_4_9.sce
new file mode 100755
index 000000000..4dd5beddb
--- /dev/null
+++ b/40/CH4/EX4.9/Exa_4_9.sce
@@ -0,0 +1,7 @@
+//inverse systems
+z=%z;
+H=(1+2*(z^(-1)))/(1+3*(z^(-1)));
+//inverse of H is
+H1=1/H
+H=1+2*(z^(-1))+3*(z^(-2));
+H1=1/H
+\ No newline at end of file
diff --git a/40/CH5/EX5.10a/Exa_5_10_a.sce b/40/CH5/EX5.10a/Exa_5_10_a.sce
new file mode 100755
index 000000000..dfd8fe815
--- /dev/null
+++ b/40/CH5/EX5.10a/Exa_5_10_a.sce
@@ -0,0 +1,22 @@
+//System Representation in various forms
+a=0.8;b=2;
+n=0:50;
+h=b*(a^n);
+//Discrete-Time Fourier transform
+K=500;
+k=0:1:K;
+w=%pi*k/K;
+H=h*exp(-%i*n'*w);
+//caluculation of phase and magnitude of h(z)
+[phase_H,m]=phasemag(H);
+H=abs(H);
+subplot(2,1,1);
+plot2d(w/%pi,H);
+xlabel('Frequency in radians')
+ylabel('abs(H)')
+title('magnitude Response')
+subplot(2,1,2)
+plot2d(w/%pi,phase_H)
+xlabel('Frequency in Radians');
+ylabel('<(H)')
+title('Phase Response')
+\ No newline at end of file
diff --git a/40/CH5/EX5.10a/Exa_5_10a.jpg b/40/CH5/EX5.10a/Exa_5_10a.jpg
new file mode 100755
index 000000000..961d5c101
--- /dev/null
+++ b/40/CH5/EX5.10a/Exa_5_10a.jpg
diff --git a/40/CH5/EX5.10b/Exa_5_10_b.sce b/40/CH5/EX5.10b/Exa_5_10_b.sce
new file mode 100755
index 000000000..e83cfffd2
--- /dev/null
+++ b/40/CH5/EX5.10b/Exa_5_10_b.sce
@@ -0,0 +1,22 @@
+//System Representation in various forms
+a=0.6;b=1;
+n=0:50;
+h=b*(a^n);
+//Discrete-Time Fourier transform
+K=500;
+k=0:1:K;
+w=%pi*k/K;
+H=h*exp(-%i*n'*w);
+//caluculation of phase and magnitude of h(z)
+[phase_H,m]=phasemag(H);
+H=abs(H);
+subplot(2,1,1);
+plot2d(w/%pi,H);
+xlabel('Frequency in radians')
+ylabel('abs(H)')
+title('magnitude Response')
+subplot(2,1,2)
+plot2d(w/%pi,phase_H)
+xlabel('Frequency in Radians');
+ylabel('<(H)')
+title('Phase Response')
+\ No newline at end of file
diff --git a/40/CH5/EX5.10b/Exa_5_10b.jpg b/40/CH5/EX5.10b/Exa_5_10b.jpg
new file mode 100755
index 000000000..58d4ed410
--- /dev/null
+++ b/40/CH5/EX5.10b/Exa_5_10b.jpg
diff --git a/40/CH5/EX5.1c/Exa_5_1c.sce b/40/CH5/EX5.1c/Exa_5_1c.sce
new file mode 100755
index 000000000..d633bd07b
--- /dev/null
+++ b/40/CH5/EX5.1c/Exa_5_1c.sce
@@ -0,0 +1,65 @@
+//DTFT of x[n]=(a)^n*u[n]
+clear;
+clc;close;
+//DTS signal
+a1=0.5;
+a2=-0.5;
+max_limit=10;
+for n=0:max_limit-1
+  x1(n+1)=(a1^n);
+  x2(n+1)=(a2^n);
+end
+n=0:max_limit-1;
+//discrete time fourier transform
+wmax=2*%pi;
+K=4;
+k=0:(K/1000):K;
+W=k*wmax/K;
+x1=x1'
+x2=x2'
+XW1=x1*exp(%i*n'*W);
+XW2=x2*exp(%i*n'*W);
+XW1_Mag=abs(XW1);
+XW2_Mag=abs(XW2);
+W=[-mtlb_fliplr(W),W(2:1001)];//omega form
+XW1_Mag=[mtlb_fliplr(XW1_Mag),XW1_Mag(2:1001)];
+XW2_Mag=[mtlb_fliplr(XW2_Mag),XW2_Mag(2:1001)];
+[XW1_phase,db]=phasemag(XW1);
+[XW2_phase,db]=phasemag(XW2);
+XW1_phase=[-mtlb_fliplr(XW1_phase),XW1_phase(2:1001)];
+XW2_phase=[-mtlb_fliplr(XW2_phase),XW2_phase(2:1001)];
+
+//plot for a>0
+figure
+subplot(3,1,1);
+plot2d3('gnn',n,x1)
+xtitle('Discrete time sequencex[n] a>0')
+subplot(3,1,2);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d3(W,XW1_Mag);
+title('magnitude Response abs(exp(jw))')
+subplot(3,1,3);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW1_phase);
+title('magnitude Response abs(exp(jw))')
+//plot for a<0
+figure
+subplot(3,1,1);
+plot2d3('gnn',n,x2);
+xtitle('Discrete Time sequence x[n] for a>0')
+subplot(3,1,2);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW2_Mag);
+title('Magnitude Response abs(X(jw))')
+subplot(3,1,3);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW2_phase);
+title('phase Response<(X(jw))')
diff --git a/40/CH5/EX5.1c/Exa_5_1c_0.jpg b/40/CH5/EX5.1c/Exa_5_1c_0.jpg
new file mode 100755
index 000000000..0723cd4fd
--- /dev/null
+++ b/40/CH5/EX5.1c/Exa_5_1c_0.jpg
diff --git a/40/CH5/EX5.1c/Exa_5_1c_1.jpg b/40/CH5/EX5.1c/Exa_5_1c_1.jpg
new file mode 100755
index 000000000..3053be702
--- /dev/null
+++ b/40/CH5/EX5.1c/Exa_5_1c_1.jpg
diff --git a/40/CH5/EX5.3a/Exa_5_3a.sce b/40/CH5/EX5.3a/Exa_5_3a.sce
new file mode 100755
index 000000000..19ebed960
--- /dev/null
+++ b/40/CH5/EX5.3a/Exa_5_3a.sce
@@ -0,0 +1,65 @@
+//DTFT of x[n]=n*(a)^n*u[n]
+clear;
+clc;close;
+//DTS signal
+a1=0.5;
+a2=-0.5;
+max_limit=10;
+for n=0:max_limit-1
+  x1(n+1)=n*(a1^n);
+  x2(n+1)=n*(a2^n);
+end
+n=0:max_limit-1;
+//discrete time fourier transform
+wmax=2*%pi;
+K=4;
+k=0:(K/1000):K;
+W=k*wmax/K;
+x1=x1';
+x2=x2';
+XW1=x1*exp(%i*n'*W);
+XW2=x2*exp(%i*n'*W);
+XW1_Mag=abs(XW1);
+XW2_Mag=abs(XW2);
+W=[-mtlb_fliplr(W),W(2:1001)];//omega form
+XW1_Mag=[mtlb_fliplr(XW1_Mag),XW1_Mag(2:1001)];
+XW2_Mag=[mtlb_fliplr(XW2_Mag),XW2_Mag(2:1001)];
+[XW1_phase,db]=phasemag(XW1);
+[XW2_phase,db]=phasemag(XW2);
+XW1_phase=[-mtlb_fliplr(XW1_phase),XW1_phase(2:1001)];
+XW2_phase=[-mtlb_fliplr(XW2_phase),XW2_phase(2:1001)];
+
+//plot for a>0
+figure
+subplot(3,1,1);
+plot2d3('gnn',n,x1)
+xtitle('Discrete time sequencex[n] a>0')
+subplot(3,1,2);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d3(W,XW1_Mag);
+title('magnitude Response abs(exp(jw))')
+subplot(3,1,3);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW1_phase);
+title('magnitude Response abs(exp(jw))')
+//plot for a<0
+figure
+subplot(3,1,1);
+plot2d3('gnn',n,x2);
+xtitle('Discrete Time sequence x[n] for a>0')
+subplot(3,1,2);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW2_Mag);
+title('Magnitude Response abs(X(jw))')
+subplot(3,1,3);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW2_phase);
+title('phase Response<(X(jw))')
diff --git a/40/CH5/EX5.3a/Exa_5_3a_0.jpg b/40/CH5/EX5.3a/Exa_5_3a_0.jpg
new file mode 100755
index 000000000..c5219738f
--- /dev/null
+++ b/40/CH5/EX5.3a/Exa_5_3a_0.jpg
diff --git a/40/CH5/EX5.3a/Exa_5_3a_1.jpg b/40/CH5/EX5.3a/Exa_5_3a_1.jpg
new file mode 100755
index 000000000..513943991
--- /dev/null
+++ b/40/CH5/EX5.3a/Exa_5_3a_1.jpg
diff --git a/40/CH5/EX5.3b/Exa_5_3_b.sce b/40/CH5/EX5.3b/Exa_5_3_b.sce
new file mode 100755
index 000000000..0305e23b3
--- /dev/null
+++ b/40/CH5/EX5.3b/Exa_5_3_b.sce
@@ -0,0 +1,65 @@
+//DTFT of x[n]=n*(a)^n*u[n]
+clear;
+clc;close;
+//DTS signal
+a1=0.5;
+a2=-0.5;
+max_limit=10;
+for n=0:max_limit-1
+  x1(n+1)=(n+1)*(a1^n);
+  x2(n+1)=(n+1)*(a2^n);
+end
+n=0:max_limit-1;
+//discrete time fourier transform
+wmax=2*%pi;
+K=4;
+k=0:(K/1000):K;
+W=k*wmax/K;
+x1=x1';
+x2=x2';
+XW1=x1*exp(%i*n'*W);
+XW2=x2*exp(%i*n'*W);
+XW1_Mag=abs(XW1);
+XW2_Mag=abs(XW2);
+W=[-mtlb_fliplr(W),W(2:1001)];//omega form
+XW1_Mag=[mtlb_fliplr(XW1_Mag),XW1_Mag(2:1001)];
+XW2_Mag=[mtlb_fliplr(XW2_Mag),XW2_Mag(2:1001)];
+[XW1_phase,db]=phasemag(XW1);
+[XW2_phase,db]=phasemag(XW2);
+XW1_phase=[-mtlb_fliplr(XW1_phase),XW1_phase(2:1001)];
+XW2_phase=[-mtlb_fliplr(XW2_phase),XW2_phase(2:1001)];
+
+//plot for a>0
+figure
+subplot(3,1,1);
+plot2d3('gnn',n,x1)
+xtitle('Discrete time sequencex[n] a>0')
+subplot(3,1,2);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d3(W,XW1_Mag);
+title('magnitude Response abs(exp(jw))')
+subplot(3,1,3);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW1_phase);
+title('magnitude Response abs(exp(jw))')
+//plot for a<0
+figure
+subplot(3,1,1);
+plot2d3('gnn',n,x2);
+xtitle('Discrete Time sequence x[n] for a>0')
+subplot(3,1,2);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW2_Mag);
+title('Magnitude Response abs(X(jw))')
+subplot(3,1,3);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW2_phase);
+title('phase Response<(X(jw))')
diff --git a/40/CH5/EX5.3b/Exa_5_3b_0.jpg b/40/CH5/EX5.3b/Exa_5_3b_0.jpg
new file mode 100755
index 000000000..1474832e8
--- /dev/null
+++ b/40/CH5/EX5.3b/Exa_5_3b_0.jpg
diff --git a/40/CH5/EX5.3b/Exa_5_3b_1.jpg b/40/CH5/EX5.3b/Exa_5_3b_1.jpg
new file mode 100755
index 000000000..cd11caa69
--- /dev/null
+++ b/40/CH5/EX5.3b/Exa_5_3b_1.jpg
diff --git a/40/CH5/EX5.3d/Exa_5_3d.jpg b/40/CH5/EX5.3d/Exa_5_3d.jpg
new file mode 100755
index 000000000..4289e45b3
--- /dev/null
+++ b/40/CH5/EX5.3d/Exa_5_3d.jpg
diff --git a/40/CH5/EX5.3d/Exa_5_3d.sce b/40/CH5/EX5.3d/Exa_5_3d.sce
new file mode 100755
index 000000000..e35c51956
--- /dev/null
+++ b/40/CH5/EX5.3d/Exa_5_3d.sce
@@ -0,0 +1,24 @@
+//DTFT of x[n]=a^abs(n)
+a=0.5;
+n=-9:9;
+x=a^abs(n);
+//Discrete time Fourier Transform
+k=0:(4/1000):4;
+w=(2*%pi*k)/4;
+xw=x*exp(%i*n'*w);
+xw_mag=real(xw);
+w=[-mtlb_fliplr(xw_mag),w(2:1001)];
+xw_mag=[mtlb_fliplr(xw_mag),xw_mag(2:1001)];
+figure
+subplot(2,1,1);
+a=gca();
+a.x_location="origin";
+a.y_location="origin";
+plot2d3('gnn',n,x);
+xtitle('discrete time sequence x[n]');
+subplot(2,1,2);
+a=gca();
+a.x_location="origin";
+a.y_location="origin";
+plot2d(w,xw_mag);
+title('discrete time fourier transform x(exp(jw))');
+\ No newline at end of file
diff --git a/40/CH5/EX5.3e/Exa_5_3e.sce b/40/CH5/EX5.3e/Exa_5_3e.sce
new file mode 100755
index 000000000..bc0ba497e
--- /dev/null
+++ b/40/CH5/EX5.3e/Exa_5_3e.sce
@@ -0,0 +1,65 @@
+//DTFT of x[n]=n*(a)^n*u[n]
+clear;
+clc;close;
+//DTS signal
+a1=0.5;
+a2=-0.5;
+max_limit=10;
+for n=0:max_limit-1
+  x1(n+1)=4*(a1^(n+3));
+  x2(n+1)=4*(a2^(n+3));
+end
+n=0:max_limit-1;
+//discrete time fourier transform
+wmax=2*%pi;
+K=4;
+k=0:(K/1000):K;
+W=k*wmax/K;
+x1=x1';
+x2=x2';
+XW1=x1*exp(%i*n'*W);
+XW2=x2*exp(%i*n'*W);
+XW1_Mag=abs(XW1);
+XW2_Mag=abs(XW2);
+W=[-mtlb_fliplr(W),W(2:1001)];//omega form
+XW1_Mag=[mtlb_fliplr(XW1_Mag),XW1_Mag(2:1001)];
+XW2_Mag=[mtlb_fliplr(XW2_Mag),XW2_Mag(2:1001)];
+[XW1_phase,db]=phasemag(XW1);
+[XW2_phase,db]=phasemag(XW2);
+XW1_phase=[-mtlb_fliplr(XW1_phase),XW1_phase(2:1001)];
+XW2_phase=[-mtlb_fliplr(XW2_phase),XW2_phase(2:1001)];
+
+//plot for a>0
+figure
+subplot(3,1,1);
+plot2d3('gnn',n,x1)
+xtitle('Discrete time sequencex[n] a>0')
+subplot(3,1,2);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d3(W,XW1_Mag);
+title('magnitude Response abs(exp(jw))')
+subplot(3,1,3);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW1_phase);
+title('magnitude Response abs(exp(jw))')
+//plot for a<0
+figure
+subplot(3,1,1);
+plot2d3('gnn',n,x2);
+xtitle('Discrete Time sequence x[n] for a>0')
+subplot(3,1,2);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW2_Mag);
+title('Magnitude Response abs(X(jw))')
+subplot(3,1,3);
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d(W,XW2_phase);
+title('phase Response<(X(jw))')
diff --git a/40/CH5/EX5.3e/Exa_5_3e_0.jpg b/40/CH5/EX5.3e/Exa_5_3e_0.jpg
new file mode 100755
index 000000000..9b58b117d
--- /dev/null
+++ b/40/CH5/EX5.3e/Exa_5_3e_0.jpg
diff --git a/40/CH5/EX5.3e/Exa_5_3e_1.jpg b/40/CH5/EX5.3e/Exa_5_3e_1.jpg
new file mode 100755
index 000000000..ec73f77a9
--- /dev/null
+++ b/40/CH5/EX5.3e/Exa_5_3e_1.jpg
diff --git a/40/CH5/EX5.4/Exa_5_4.sce b/40/CH5/EX5.4/Exa_5_4.sce
new file mode 100755
index 000000000..c04a7543a
--- /dev/null
+++ b/40/CH5/EX5.4/Exa_5_4.sce
@@ -0,0 +1,20 @@
+//DTfT of periodic signals
+x=[3 2 1 2];//one period of signal
+n=0:3;
+k=0:3;
+x1=x*exp(%i*n'*2*k*%pi/4)
+dtftx=abs(x1)
+x=[3 2 1 2 3 2 1 2 3];
+n=-4:4;
+a=gca();
+a.y_location="origin";
+a.x_location="origin";
+plot2d3('gnn',n,x);
+xtitle('discrete periodic time signal');
+x2=[dtftx dtftx 8];
+a=gca();
+xset('window',1);
+a.x_location="origin";
+a.y_location="origin";
+plot2d3('gnn',n,x2);
+xtitle('DTFT of discrete periodic signal');
+\ No newline at end of file
diff --git a/40/CH5/EX5.4/Exa_5_4_0.jpg b/40/CH5/EX5.4/Exa_5_4_0.jpg
new file mode 100755
index 000000000..efd03636f
--- /dev/null
+++ b/40/CH5/EX5.4/Exa_5_4_0.jpg
diff --git a/40/CH5/EX5.4/Exa_5_4_1.jpg b/40/CH5/EX5.4/Exa_5_4_1.jpg
new file mode 100755
index 000000000..f2557d814
--- /dev/null
+++ b/40/CH5/EX5.4/Exa_5_4_1.jpg
diff --git a/40/CH5/EX5.5/Exa_5_5.sce b/40/CH5/EX5.5/Exa_5_5.sce
new file mode 100755
index 000000000..0ad017d37
--- /dev/null
+++ b/40/CH5/EX5.5/Exa_5_5.sce
@@ -0,0 +1,7 @@
+x=[1 0 2 0 3];//one period of signal
+n=0:4;
+k=0:4;
+x1=x*exp(%i*n'*2*k*%pi/4)
+DTFTx=abs(x1)
+DFT=dft(x,-1)
+DFS=DFT/5
+\ No newline at end of file
diff --git a/40/CH5/EX5.7/Exa_5_7.jpg b/40/CH5/EX5.7/Exa_5_7.jpg
new file mode 100755
index 000000000..79b7f27dc
--- /dev/null
+++ b/40/CH5/EX5.7/Exa_5_7.jpg
diff --git a/40/CH5/EX5.7/Exa_5_7.sce b/40/CH5/EX5.7/Exa_5_7.sce
new file mode 100755
index 000000000..aed9a6ed3
--- /dev/null
+++ b/40/CH5/EX5.7/Exa_5_7.sce
@@ -0,0 +1,26 @@
+a=0.5;b=1;
+n=0:50;
+h=b*(a^n);
+//Discrete-Time Fourier transform
+K=500;
+k=-250:1:250;
+w=%pi*k/K;
+H=h*exp(-%i*n'*w);
+//caluculation of phase and magnitude of h(z)
+[phase_H,m]=phasemag(H);
+H=abs(H);
+a=gca();
+subplot(2,1,1);
+a.y_location="origin";
+plot2d(w/%pi,H);
+xlabel('Frequency in radians')
+ylabel('abs(H)')
+title('magnitude Response')
+subplot(2,1,2);
+a=gca();
+a.x_location="origin";
+a.y_location="origin";
+plot2d(w/(2*%pi),phase_H)
+xlabel('Frequency in Radians');
+ylabel('<(H)')
+title('Phase Response'))
+\ No newline at end of file
diff --git a/40/CH5/EX5.8a/Exa_5_8a.jpg b/40/CH5/EX5.8a/Exa_5_8a.jpg
new file mode 100755
index 000000000..810376248
--- /dev/null
+++ b/40/CH5/EX5.8a/Exa_5_8a.jpg
diff --git a/40/CH5/EX5.8a/Exa_5_8a.sce b/40/CH5/EX5.8a/Exa_5_8a.sce
new file mode 100755
index 000000000..c4b05e45a
--- /dev/null
+++ b/40/CH5/EX5.8a/Exa_5_8a.sce
@@ -0,0 +1,26 @@
+//DTFT in system analysis
+a=0.5;b=1;
+n=0:50;
+h=b*(a^n);
+//Discrete-Time Fourier transform
+K=500;
+k=0:1:K;
+w=%pi*k/K;
+H=h*exp(-%i*n'*w);
+//x[n] is given as (a)^n*u[n]
+xw=h*exp(-%i*n'*w);
+for i=1:501
+    y(i)=H(i)*xw(i);
+end
+[phase_y,m]=phasemag(y);
+y=real(y);
+subplot(2,1,1)
+plot2d(w/%pi,y);
+xlabel('Frequency in radians')
+ylabel('abs(y)')
+title('magnitude Response')
+subplot(2,1,2)
+plot2d(w/%pi,phase_y)
+xlabel('Frequency in Radians');
+ylabel('<(y)')
+title('Phase Response')
+\ No newline at end of file
diff --git a/40/CH5/EX5.8b/Exa_5_8b.jpg b/40/CH5/EX5.8b/Exa_5_8b.jpg
new file mode 100755
index 000000000..2e6dbdf8d
--- /dev/null
+++ b/40/CH5/EX5.8b/Exa_5_8b.jpg
diff --git a/40/CH5/EX5.8b/Exa_5_8b.sce b/40/CH5/EX5.8b/Exa_5_8b.sce
new file mode 100755
index 000000000..9e67504ee
--- /dev/null
+++ b/40/CH5/EX5.8b/Exa_5_8b.sce
@@ -0,0 +1,26 @@
+a=0.5;b=1;
+n=0:50;
+h=4*(a^n);
+//Discrete-Time Fourier transform
+K=500;
+k=0:1:K;
+w=%pi*k/K;
+H=h*exp(-%i*n'*w);
+//x[n] is given as (a)^n*u[n]
+x=4*[ones(1:51)];
+xw=x*exp(%i*n'*w);
+for i=1:501
+    y(i)=H(i)*xw(i);
+end
+[phase_y,m]=phasemag(y);
+y=real(y);
+subplot(2,1,1);
+plot2d(w/%pi,y);
+xlabel('Frequency in radians')
+ylabel('abs(y)')
+title('magnitude Response')
+subplot(2,1,2)
+plot2d(w/%pi,phase_y)
+xlabel('Frequency in Radians');
+ylabel('<(y)')
+title('Phase Response')
+\ No newline at end of file
diff --git a/40/CH5/EX5.9a/Exa_5_9a.jpg b/40/CH5/EX5.9a/Exa_5_9a.jpg
new file mode 100755
index 000000000..f2f0d0e24
--- /dev/null
+++ b/40/CH5/EX5.9a/Exa_5_9a.jpg
diff --git a/40/CH5/EX5.9a/Exa_5_9a.sce b/40/CH5/EX5.9a/Exa_5_9a.sce
new file mode 100755
index 000000000..46f3540d1
--- /dev/null
+++ b/40/CH5/EX5.9a/Exa_5_9a.sce
@@ -0,0 +1,19 @@
+//DTFT and steady state response 
+a=0.5,b=1;F=0.25;
+n=0:(5/1000):5;
+h=(a^n);
+x=10*cos(0.5*%pi*n'+%pi/3);
+H=h*exp(-%i*n'*F);
+Yss=H*x;
+[phase_Yss,m]=phasemag(Yss);
+Yss=real(Yss);
+subplot(2,1,1)
+plot2d(n,Yss);
+xlabel('Frequency in radians')
+ylabel('abs(Yss)')
+title('magnitude Response')
+subplot(2,1,2)
+plot2d(n,phase_Yss)
+xlabel('Frequency in Radians');
+ylabel('<(y)')
+title('Phase Response')
+\ No newline at end of file
diff --git a/40/CH5/EX5.9b/Exa_5_9b.sce b/40/CH5/EX5.9b/Exa_5_9b.sce
new file mode 100755
index 000000000..96b98078f
--- /dev/null
+++ b/40/CH5/EX5.9b/Exa_5_9b.sce
@@ -0,0 +1,7 @@
+//DTFT and steady state response 
+a=0.8,b=1;F=0;
+n=0:50;
+h=(a^n);
+x=4*[ones(1:10)];
+H=h*exp(-%i*n'*F)
+Yss=H*x
+\ No newline at end of file
diff --git a/40/CH6/EX6.1/Exa_6_1.jpg b/40/CH6/EX6.1/Exa_6_1.jpg
new file mode 100755
index 000000000..c141e4c3d
--- /dev/null
+++ b/40/CH6/EX6.1/Exa_6_1.jpg
diff --git a/40/CH6/EX6.1/Exa_6_1.sce b/40/CH6/EX6.1/Exa_6_1.sce
new file mode 100755
index 000000000..ec8ea9cb8
--- /dev/null
+++ b/40/CH6/EX6.1/Exa_6_1.sce
@@ -0,0 +1,24 @@
+//The minimum phase concept
+z=%z;
+F=0:(0.5/400):0.5;
+z=exp(%i*2*%pi*F);
+for i=1:401
+H1Z(i)=((z(i)-1/2)*(z(i)-1/4))/((z(i)-1/3)*(z(i)-1/5));
+end
+for i=1:401
+H2Z(i)=(((-1/2)*z(i)+1)*(z(i)-1/4))/((z(i)-1/3)*(z(i)-1/5));
+end
+for i=1:401
+H3Z(i)=(((-1/2)*z(i)+1)*((-1/4)*z(i)+1))/((z(i)-1/3)*(z(i)-1/5));
+end
+[phase_H1Z,m]=phasemag(H1Z);
+[phase_H2Z,m]=phasemag(H2Z);
+[phase_H3Z,m]=phasemag(H3Z);
+a=gca();
+a.x_location="origin";
+xlabel('Digital Frequency F');
+ylabel('phase[degrees]');
+xtitle('phase of three filters');
+plot2d(F,phase_H1Z,rect=[0,-200,0.5,200]);
+plot2d(F,phase_H2Z,rect=[0,-200,0.5,200]);
+plot2d(F,phase_H3Z,rect=[0,-200,0.5,200]);
+\ No newline at end of file
diff --git a/40/CH6/EX6.4/Exa_6_4.sce b/40/CH6/EX6.4/Exa_6_4.sce
new file mode 100755
index 000000000..04548d460
--- /dev/null
+++ b/40/CH6/EX6.4/Exa_6_4.sce
@@ -0,0 +1,14 @@
+//linear phase filters
+z=%z
+H1Z=((z^3)+2*(z^2)+2*z+1)/(z^3);
+//from pole zero diagram its not a linear phase filter
+H2Z=(z^4+4.25*z^2+1)/(z^4);
+xset('window',1);
+plzr(H2Z);
+//from pole zero diagram and LPF
+// characteristics its a linear phase filter
+H3Z=((z^4+2.5*z^3-2.5*z-1)/(z^4));
+xset('window',2);
+plzr(H3Z);
+//from pole zero diagram and LPF
+// characteristics its a linear phase filter
+\ No newline at end of file
diff --git a/40/CH6/EX6.4/Exa_6_4_1.jpg b/40/CH6/EX6.4/Exa_6_4_1.jpg
new file mode 100755
index 000000000..fd0732194
--- /dev/null
+++ b/40/CH6/EX6.4/Exa_6_4_1.jpg
diff --git a/40/CH6/EX6.4/Exa_6_4_2.jpg b/40/CH6/EX6.4/Exa_6_4_2.jpg
new file mode 100755
index 000000000..4f4f5da48
--- /dev/null
+++ b/40/CH6/EX6.4/Exa_6_4_2.jpg
diff --git a/40/CH6/EX6.6/Exa_6_6.jpg b/40/CH6/EX6.6/Exa_6_6.jpg
new file mode 100755
index 000000000..ea5dd2a8d
--- /dev/null
+++ b/40/CH6/EX6.6/Exa_6_6.jpg
diff --git a/40/CH6/EX6.6/Exa_6_6.sce b/40/CH6/EX6.6/Exa_6_6.sce
new file mode 100755
index 000000000..0a4466ea7
--- /dev/null
+++ b/40/CH6/EX6.6/Exa_6_6.sce
@@ -0,0 +1,18 @@
+//Frequency Response and filter characteristics
+z=%z;
+F=0:(0.5/200):0.5;
+z=exp(%i*2*%pi*F);
+H1=(1/3)*(z+1+z^-1);
+H2=(z/4)+(1/2)+(1/4)*(z^-1);
+H1=abs(H1);
+H2=abs(H2);
+a=gca();
+a.x_location="origin";
+subplot(211);
+plot2d(F,H1);
+xlabel('Digital frequency F');
+ylabel('impuse function H1(f)');
+subplot(212);
+plot2d(F,H2);
+xlabel('Digital frequency F');
+ylabel('impuse function H1(f)');
+\ No newline at end of file
diff --git a/40/CH6/EX6.7a/Exa_6_7a.sce b/40/CH6/EX6.7a/Exa_6_7a.sce
new file mode 100755
index 000000000..930df321e
--- /dev/null
+++ b/40/CH6/EX6.7a/Exa_6_7a.sce
@@ -0,0 +1,18 @@
+z=%z;
+s=%s;
+F=0:(0.5/400):0.5;
+s=exp(%i*2*%pi*F);
+H1Z=(z^4+1)/(z^4+1.6982*z^2+0.7210);
+for i=1:401
+    H1(i)=(s(i)^4+1)/(s(i)^4+1.6982*s(i)^2+0.7210);
+end
+H1=abs(H1);
+plzr(H1Z);
+a=gca();
+xset('window',1);
+a.x_location="origin";
+a.y_location="origin";
+plot2d(F,H1)
+xlabel('Digital frequency F');
+ylabel('magnitude');
+xtitle('Magnitude spectrum of bandpass filter');
diff --git a/40/CH6/EX6.7a/Exa_6_7a_0.jpg b/40/CH6/EX6.7a/Exa_6_7a_0.jpg
new file mode 100755
index 000000000..bf627aa02
--- /dev/null
+++ b/40/CH6/EX6.7a/Exa_6_7a_0.jpg
diff --git a/40/CH6/EX6.7a/Exa_6_7a_1.jpg b/40/CH6/EX6.7a/Exa_6_7a_1.jpg
new file mode 100755
index 000000000..3dc90ce8b
--- /dev/null
+++ b/40/CH6/EX6.7a/Exa_6_7a_1.jpg
diff --git a/40/CH6/EX6.7b/Exa_6_7b.sce b/40/CH6/EX6.7b/Exa_6_7b.sce
new file mode 100755
index 000000000..8d9b05069
--- /dev/null
+++ b/40/CH6/EX6.7b/Exa_6_7b.sce
@@ -0,0 +1,18 @@
+z=%z;
+s=%s;
+F=0:(0.5/400):0.5;
+s=exp(%i*2*%pi*F);
+H1Z=(z^2+1-0.618*z)/(z^2-0.5857*z+0.898);
+for i=1:401
+    H1(i)=(s(i)^2+1-0.618*s(i))/(s(i)^2-0.5857*s(i)+0.898);
+end
+H1=abs(H1);
+plzr(H1Z);
+a=gca();
+xset('window',1);
+a.x_location="origin";
+a.y_location="origin";
+plot2d(F,H1)
+xlabel('Digital frequency F');
+ylabel('magnitude');
+xtitle('Magnitude spectrum of bandpass filter');
diff --git a/40/CH6/EX6.7b/Exa_6_7b_0.jpg b/40/CH6/EX6.7b/Exa_6_7b_0.jpg
new file mode 100755
index 000000000..db9eb323e
--- /dev/null
+++ b/40/CH6/EX6.7b/Exa_6_7b_0.jpg
diff --git a/40/CH6/EX6.7b/Exa_6_7b_1.jpg b/40/CH6/EX6.7b/Exa_6_7b_1.jpg
new file mode 100755
index 000000000..7680db94e
--- /dev/null
+++ b/40/CH6/EX6.7b/Exa_6_7b_1.jpg
diff --git a/40/CH6/EX6.8/Exa_6_8.sce b/40/CH6/EX6.8/Exa_6_8.sce
new file mode 100755
index 000000000..811691ac4
--- /dev/null
+++ b/40/CH6/EX6.8/Exa_6_8.sce
@@ -0,0 +1,28 @@
+//Digital Resonator design with peak gain 50 HZ 
+//and 3 db bandwidth of 6HZ at sampling of 300 HZ
+clf();
+s=%s;
+F=0:150;
+f=F/300;
+s=exp(%i*2*%pi*f);
+for i=1:151
+    H1(i)=(0.1054*(s(i)^2))/(s(i)^2-0.9372*s(i)+0.8783);
+end
+H1=abs(H1);
+H2=H1(40:60);
+F1=40:60;
+f1=F1/300;
+a=gca();
+a.x_location="origin";
+a.y_location="origin";
+plot2d(F,H1)
+xlabel('Analog frequency F');
+ylabel('magnitude');
+xtitle('Magnitude spectrum of digital resonator with peak 50HZ');
+xset('window',1);
+a.x_location="origin";
+a.y_location="origin";
+plot2d(F1,H2)
+xlabel('Analog frequency F');
+ylabel('magnitude');
+xtitle('passband detail');
+\ No newline at end of file
diff --git a/40/CH6/EX6.8/Exa_6_8_0.jpg b/40/CH6/EX6.8/Exa_6_8_0.jpg
new file mode 100755
index 000000000..87a34442c
--- /dev/null
+++ b/40/CH6/EX6.8/Exa_6_8_0.jpg
diff --git a/40/CH6/EX6.8/Exa_6_8_1.jpg b/40/CH6/EX6.8/Exa_6_8_1.jpg
new file mode 100755
index 000000000..e6e818d46
--- /dev/null
+++ b/40/CH6/EX6.8/Exa_6_8_1.jpg
diff --git a/40/CH6/EX6.9/Exa_6_9.sce b/40/CH6/EX6.9/Exa_6_9.sce
new file mode 100755
index 000000000..3e8500a97
--- /dev/null
+++ b/40/CH6/EX6.9/Exa_6_9.sce
@@ -0,0 +1,29 @@
+//Periodic notch filter design at 60 HZ and sampling frequency 300HZ
+z=%z;
+f=0:(0.5/400):0.5;
+z1=exp(%i*2*%pi*f);
+for i=1:401
+    H1Z(i)=(z1(i)^5-1)/((z1(i)^5)-(0.9^5));
+    H2Z(i)=(z1(i)^5-1)/((z1(i)^5)-(0.99^5));
+end
+H1Z=abs(H1Z);
+H2Z=abs(H2Z);
+N1z=(1-z^-5)/(1-z^-1);
+H3z=(N1z)/(horner(N1z,z/0.9));
+H4z=(N1z)/(horner(N1z,z/0.99));
+H3z=horner(H3z,z1);
+H4z=horner(H4z,z1);
+a=gca();
+a.x_location="origin";
+a.y_location="origin";
+plot2d(f,H1Z);
+plot2d(f,H2Z);
+xlabel('Digital frequency f');
+ylabel('magnitude');
+xtitle('Periodic Notch Filter N=5,R=0.9,0.99');
+xset('window',1);
+plot2d(f,H3z);
+plot2d(f,H4z);
+xlabel('Digital frequency f');
+ylabel('magnitude');
+xtitle('Notch Filter that also passes DC N=5,R=0.9,0.99');
diff --git a/40/CH6/EX6.9/Exa_6_9_0.jpg b/40/CH6/EX6.9/Exa_6_9_0.jpg
new file mode 100755
index 000000000..0831aeb28
--- /dev/null
+++ b/40/CH6/EX6.9/Exa_6_9_0.jpg
diff --git a/40/CH6/EX6.9/Exa_6_9_1.jpg b/40/CH6/EX6.9/Exa_6_9_1.jpg
new file mode 100755
index 000000000..f92596e19
--- /dev/null
+++ b/40/CH6/EX6.9/Exa_6_9_1.jpg
diff --git a/40/CH7/EX7.10/Exa_7_10.sce b/40/CH7/EX7.10/Exa_7_10.sce
new file mode 100755
index 000000000..b0f184d42
--- /dev/null
+++ b/40/CH7/EX7.10/Exa_7_10.sce
@@ -0,0 +1,23 @@
+//ADC considerations
+//(a)Aperture time TA
+B=12;
+fo=15000;//band limited frquency
+TAm=(1/((2^B)))/(%pi*fo);
+TAm=TAm*10^9
+//Hence TA must satisfy TA<=TAm nano sec
+//(b)conversion time of quantizer
+TA=4*10^-9;
+TH=10*10^-6;//hold time
+S=30*10^3;
+TCm=1/S-TA-TH;
+TCm=TCm*10^6
+//Hence TC must satisfy TC<=TCm micro sec
+//(c)Holding capacitance C
+Vo=10;
+TH=10*10^-6;
+B=12;
+R=10^6;//input resistance
+delv=Vo/(2^(B+1));
+Cm=(Vo*TH)/(R*delv);
+Cm=Cm*10^9
+//Hence C must satisfy C>=Cm nano farad
+\ No newline at end of file
diff --git a/40/CH7/EX7.11/Exa_7_11.sce b/40/CH7/EX7.11/Exa_7_11.sce
new file mode 100755
index 000000000..6df3d2b96
--- /dev/null
+++ b/40/CH7/EX7.11/Exa_7_11.sce
@@ -0,0 +1,14 @@
+//Anti Aliasing filter considerations
+//minimum stop band attenuation As
+B=input('enter no. of bits');//no. of samples
+n=input('enter band width in KHZ');
+As=20*log10(2^B*sqrt(6))
+//nomalised frequency
+Vs=(10^(0.1*As)-1)^(1/(2*n))
+fp=4;//pass edge frequency
+fs=Vs*fp//stop band frquency
+S=2*fs//sampling frequency
+fa=S-fp//aliaed frequency
+Va=fa/fp;
+//Attenuation at aliased frequency
+Aa=10*log10(1+Va^(2*n))
+\ No newline at end of file
diff --git a/40/CH7/EX7.12/Exa_7_12.jpg b/40/CH7/EX7.12/Exa_7_12.jpg
new file mode 100755
index 000000000..5bc821696
--- /dev/null
+++ b/40/CH7/EX7.12/Exa_7_12.jpg
diff --git a/40/CH7/EX7.12/Exa_7_12.sce b/40/CH7/EX7.12/Exa_7_12.sce
new file mode 100755
index 000000000..5a246a91c
--- /dev/null
+++ b/40/CH7/EX7.12/Exa_7_12.sce
@@ -0,0 +1,28 @@
+//Anti Imaging Filter considerations
+Ap=0.5;//passband attenuation
+fp=20;//passband edge frequency
+As=60;//stopband attenuation
+S=42.1;
+fs=S-fp;//stopband edge frequency
+e=sqrt(10^(0.1*Ap)-1);
+e1=sqrt(10^(0.1*As)-1);
+n=(log10(e1/e))/(log10(fs/fp));
+n=ceil(n)//design of nth order butworth filter
+//(b)Assuming Zero-order hold sampling
+S1=176.4;
+fs1=S1-fp;
+Ap=0.316;
+e2=sqrt(10^(0.1*Ap)-1);
+n1=(log10(e1/e2))/(log(fs1/fp));//new order of butworth filter
+n1=ceil(n1)
+f=0:100;
+x=abs(sinc(f*%pi/S));
+f1=0:500;
+x1=abs(sinc(f1*%pi/S1));
+a=gca();
+subplot(211);
+plot2d(f,x);
+xtitle("spectra under normal sampling condition","f(kHZ)","sinc(f/s1)");
+subplot(212);
+plot2d(f1,x1);
+xtitle("spectra under over sampling condition","f(kHZ)","sinc(f/s1)");
+\ No newline at end of file
diff --git a/40/CH7/EX7.3/Exa_7_3.sce b/40/CH7/EX7.3/Exa_7_3.sce
new file mode 100755
index 000000000..83e357e78
--- /dev/null
+++ b/40/CH7/EX7.3/Exa_7_3.sce
@@ -0,0 +1,16 @@
+//Sampling Oscilloscope Concepts
+fo=100;a=50;
+s=(a-1)*fo/a;
+B=100-s;
+i=s/(2*B);
+i=ceil(i);
+disp(i,'The sampling frequency can at max divided by i');
+disp(s,2*B,'range of sampling rate is between s and 2*B');
+fo1=100;
+a=50;
+s1=(a-1)*fo1/a;
+B1=400-4*s1;
+j=s1/(2*B1);
+j=ceil(j);
+disp(j,'The sampling frequency can at max divided by j');
+disp(s1,2*B1,'range of sampling rate is between s1 and 2*B1');
+\ No newline at end of file
diff --git a/40/CH7/EX7.4/Exa_7_4.sce b/40/CH7/EX7.4/Exa_7_4.sce
new file mode 100755
index 000000000..a8fa4fd96
--- /dev/null
+++ b/40/CH7/EX7.4/Exa_7_4.sce
@@ -0,0 +1,26 @@
+//sampling of bandpass signals
+fc=4;fl=6;
+B=fl-fc;
+xt=[0 1 2 1];
+xtt=[0 1 2];
+a=0;b=1;c=2;
+xta=[xt];
+xtb=[0 0 2 1 0];
+xtc=[0 0 0 2 1 0];
+xt1=[xta xta xta]; 
+xt2=[xtb xtb(length(xtb):-1:2) xtb(2:length(xtb)) xtb(length(xtb):-1:2)];
+xt3=[xtc(length(xtc):-1:2) xtc(3:length(xtc)) zeros(1:7) xtc(length(xtc):-1:2) xtc(3:length(xtc))];
+f1=0:length(xt1)-1;
+f2=[0 1 1.001 2:6 6.001 7 7.001 8:12 12.001];
+f3=[-10:-8 -7.99 -7:-6 -5.99 -5:6 6.01 7:8 8.01 9:10];
+subplot(211);
+plot2d(f1,xt1);
+xtitle("spectrum of signal sampled at 4KHZ");
+subplot(212);
+plot2d(f2,xt2);
+xtitle("spectrum of signal sampled at 7KHZ");
+xset('window',1);
+b=gca();
+b.y_location="origin"
+plot2d(f3,xt3);
+xtitle("spectrum of signal sampled at 14KHZ");
+\ No newline at end of file
diff --git a/40/CH7/EX7.4/Exa_7_4_0.jpg b/40/CH7/EX7.4/Exa_7_4_0.jpg
new file mode 100755
index 000000000..c7d28890d
--- /dev/null
+++ b/40/CH7/EX7.4/Exa_7_4_0.jpg
diff --git a/40/CH7/EX7.4/Exa_7_4_1.jpg b/40/CH7/EX7.4/Exa_7_4_1.jpg
new file mode 100755
index 000000000..f5273ae82
--- /dev/null
+++ b/40/CH7/EX7.4/Exa_7_4_1.jpg
diff --git a/40/CH7/EX7.6/Exa_7_6.sce b/40/CH7/EX7.6/Exa_7_6.sce
new file mode 100755
index 000000000..aa3b57c4b
--- /dev/null
+++ b/40/CH7/EX7.6/Exa_7_6.sce
@@ -0,0 +1,24 @@
+//signal reconstruction from samples
+//(a)By step interpolation method
+x=[-1 2 3 2];
+t=2.5;
+ts=1;
+t1=ceil(t);
+t2=floor(t);
+x1t=x(t2)
+//(b)By linear interpolation method
+x2t=(x(t1)+x(t2))/2
+//(c)By sinc interpolation method
+x3t=0;x1=[1 2 3 4];
+for k=1:4
+    x3t=x3t+(x1(k)*sinc(%pi*(t-(k-1))));
+end
+x3t//sinc interpolated value of x(2.5)
+//(d)raised cosine interpolation method
+x4t=0;
+for k=1:4
+    p=(cos(0.5*%pi*(t-k+1))/(1-(t-k+1)^2));
+    xt=x1(k)*sinc(%pi*(t-k+1))*p;
+    x4t=x4t+xt;
+end
+x4t//raised cosine interpolated value of x(2.5)
+\ No newline at end of file
diff --git a/40/CH7/EX7.7/Exa_7_7.sce b/40/CH7/EX7.7/Exa_7_7.sce
new file mode 100755
index 000000000..fcaed3724
--- /dev/null
+++ b/40/CH7/EX7.7/Exa_7_7.sce
@@ -0,0 +1,30 @@
+//Zero interpolation and spectrum replication
+XF=[0 1 2 1];
+X1F=[XF XF XF 0];
+YF=[X1F X1F];
+DF=0.5*[XF XF 0];
+GF=0.5*[XF 0 XF 0 XF 0];
+f=-0.2:0.1:1;
+f1=-0.1:0.05:1.15;
+f2=-0.4:0.2:1.2;
+f3=-0.2:0.1:1.2;
+length(f3),length(GF)
+a=gca();
+a.y_location="origin";
+subplot(211);
+plot2d(f,X1F);
+ylabel('X1F');
+subplot(212);
+a.y_location="origin";
+plot2d(f1,YF);
+ylabel('YF');
+xset('window',1);
+b=gca();
+b.y_location="origin";
+subplot(211);
+plot2d(f2,DF);
+ylabel('DF');
+subplot(212);
+b.y_location="origin";
+plot2d(f3,GF);
+ylabel('GF');
+\ No newline at end of file
diff --git a/40/CH7/EX7.7/Exa_7_7_0.jpg b/40/CH7/EX7.7/Exa_7_7_0.jpg
new file mode 100755
index 000000000..5e7104cbe
--- /dev/null
+++ b/40/CH7/EX7.7/Exa_7_7_0.jpg
diff --git a/40/CH7/EX7.7/Exa_7_7_1.jpg b/40/CH7/EX7.7/Exa_7_7_1.jpg
new file mode 100755
index 000000000..636861653
--- /dev/null
+++ b/40/CH7/EX7.7/Exa_7_7_1.jpg
diff --git a/40/CH7/EX7.8/Exa_7_8.sce b/40/CH7/EX7.8/Exa_7_8.sce
new file mode 100755
index 000000000..f2738c7e7
--- /dev/null
+++ b/40/CH7/EX7.8/Exa_7_8.sce
@@ -0,0 +1,31 @@
+clf();
+X=[0 0.5 1 0.5];
+XF=[X 0];
+WF=[X X X 0];
+f=-0.5:0.25:0.5;
+f1=-0.75:0.125:0.75;
+HF=[0 1 1 1 0];
+f2=[-0.126,-0.125:0.125:0.125,0.126];
+for i=1:5
+    YF(i)=WF(i)*HF(i);
+end
+f3=[-0.126 -0.125 0 0.125 0.126];
+a=gca();
+a.y_location="origin";
+subplot(211);
+plot2d(f,XF);
+xtitle('spectrum of XF');
+a.y_location="origin";
+subplot(212);
+plot2d(f1,WF);
+xtitle('spectrum of WF');
+xset('window',1);
+b=gca();
+b.y_location="origin";
+subplot(211);
+plot2d(f2,HF);
+xtitle('spectrum of HF');
+b.y_location="origin";
+subplot(212);
+plot2d(f3,YF);
+xtitle('spectrum of YF');
+\ No newline at end of file
diff --git a/40/CH7/EX7.8/Exa_7_8_0.jpg b/40/CH7/EX7.8/Exa_7_8_0.jpg
new file mode 100755
index 000000000..d02ed0911
--- /dev/null
+++ b/40/CH7/EX7.8/Exa_7_8_0.jpg
diff --git a/40/CH7/EX7.8/Exa_7_8_1.jpg b/40/CH7/EX7.8/Exa_7_8_1.jpg
new file mode 100755
index 000000000..309a35e07
--- /dev/null
+++ b/40/CH7/EX7.8/Exa_7_8_1.jpg
diff --git a/40/CH7/EX7.9/Exa_7_9.sce b/40/CH7/EX7.9/Exa_7_9.sce
new file mode 100755
index 000000000..dd88eaf73
--- /dev/null
+++ b/40/CH7/EX7.9/Exa_7_9.sce
@@ -0,0 +1,21 @@
+//(a)Quantisation effects
+sig=0.005;
+D=4;
+B=log2(D/(sig*sqrt(12)));//no.of samples
+//value of B to ensure quantisation error to 5mv
+//(b)Quantisation error and noise
+xn=0:0.2:2.0;
+xqn=[0 0 0.5 0.5 1 1 1 1.5 1.5 2 2];
+en=xn-xqn;//quantization error
+//Quantisation signal top noise ratio
+x=0;e=0;
+for i=1:length(xn)
+    x=x+xn(i)^2;
+    e=e+en(i)^2;
+end
+//method 1
+SNRQ=10*log10(x/e)
+//method 2
+SNRQ=10*log10(x/length(xn))+10.8+20*log10(4)-20*log10(2)
+SNRS=10*log10(1.33)+10*log10(12)+20*log10(4)-20*log10(2)
+//from results we see that SNRS is statistical estimate
+\ No newline at end of file
diff --git a/40/CH8/EX8.1/Exa_8_1.sce b/40/CH8/EX8.1/Exa_8_1.sce
new file mode 100755
index 000000000..000b8b907
--- /dev/null
+++ b/40/CH8/EX8.1/Exa_8_1.sce
@@ -0,0 +1,6 @@
+//DFT from defining relation
+//N-point DFT
+x=[1 2 1 0];
+XDFT=dft(x,-1);
+disp(XDFT,'The DFT of x[n] is');
+//DFT of periodic signal x with period N=4
+\ No newline at end of file
diff --git a/40/CH8/EX8.10/Exa_8_10.sce b/40/CH8/EX8.10/Exa_8_10.sce
new file mode 100755
index 000000000..d9676ae26
--- /dev/null
+++ b/40/CH8/EX8.10/Exa_8_10.sce
@@ -0,0 +1,9 @@
+//DFS of sampled periodic signals
+xn=[0 ones(2:16) 0 -ones(18:32)];
+XDFS=0.032*dft(xn,-1);
+for i=1:length(XDFS)
+    if (abs(XDFS(i))<0.000001) then
+        XDFS(i)=0;
+    end
+end
+disp(XDFS,'The DFS of x[n] is');
+\ No newline at end of file
diff --git a/40/CH8/EX8.11/Exa_8_11.sce b/40/CH8/EX8.11/Exa_8_11.sce
new file mode 100755
index 000000000..5b086398e
--- /dev/null
+++ b/40/CH8/EX8.11/Exa_8_11.sce
@@ -0,0 +1,27 @@
+//Effects of leakage
+n1=0:0.005:0.1;
+n2=0:0.005:0.125;
+n3=0:0.005:1.125;
+xt1=(2*cos(20*%pi*n1')+5*cos(100*%pi*n1'));
+xt2=(2*cos(20*%pi*n2')+5*cos(100*%pi*n2'));
+xt3=(2*cos(20*%pi*n3')+5*cos(100*%pi*n3'));
+XDFS1=abs(dft(xt1,-1))/20;
+XDFS2=abs(dft(xt2,-1))/25;
+XDFS3=abs(dft(xt3,-1))/225;
+f1=0:5:100;
+f2=0:4:100;
+f3=0:100/225:100;
+a=gca();
+a.x_location="origin";
+plot2d3('gnn',f1,XDFS1);
+xlabel('analog frequency');
+ylabel('Magnitude');
+xset('window',1);
+subplot(211);
+plot2d3('gnn',f2,XDFS2);
+xlabel('analog frequency');
+ylabel('Magnitude');
+subplot(212);
+plot2d3('gnn',f3,XDFS3);
+xlabel('analog frequency');
+ylabel('Magnitude');
+\ No newline at end of file
diff --git a/40/CH8/EX8.11/Exa_8_11_0.jpg b/40/CH8/EX8.11/Exa_8_11_0.jpg
new file mode 100755
index 000000000..776d7a686
--- /dev/null
+++ b/40/CH8/EX8.11/Exa_8_11_0.jpg
diff --git a/40/CH8/EX8.11/Exa_8_11_1.jpg b/40/CH8/EX8.11/Exa_8_11_1.jpg
new file mode 100755
index 000000000..e0746b696
--- /dev/null
+++ b/40/CH8/EX8.11/Exa_8_11_1.jpg
diff --git a/40/CH8/EX8.15a/Exa_8_15a.sce b/40/CH8/EX8.15a/Exa_8_15a.sce
new file mode 100755
index 000000000..5905d9dbe
--- /dev/null
+++ b/40/CH8/EX8.15a/Exa_8_15a.sce
@@ -0,0 +1,12 @@
+//overlapp-add and overlap-save methods of convolution
+//overlap-add method
+xn=[1 2 3 3 4 5];
+xon=[1 2 3];
+x1n=[3 4 5];
+hn=[1 1 1];
+yon=convol(xon,hn);
+y1n=convol(x1n,hn);
+yon=[yon,0,0,0];
+y1n=[0,0,0,y1n];
+yn=yon+y1n
+yn1=convol(xn,hn) 
+\ No newline at end of file
diff --git a/40/CH8/EX8.15b/Exa_8_15b.sce b/40/CH8/EX8.15b/Exa_8_15b.sce
new file mode 100755
index 000000000..b72139b8c
--- /dev/null
+++ b/40/CH8/EX8.15b/Exa_8_15b.sce
@@ -0,0 +1,14 @@
+//(b)overlap-save method
+xn=[1 2 3 3 4 5];
+hn=[1 1 1];
+xon=[0 0 1 2 3];
+x1n=[2 3 3 4 5];
+x2n=[4 5 0 0 0];
+yon=convol(xon,hn);
+y1n=convol(x1n,hn);
+y2n=convol(x2n,hn);
+yno=yon(3:5);
+yn1=y1n(3:5);
+yn2=y2n(3:5);
+yn=[yno yn1 yn2]
+YN=convol(xn,hn)
+\ No newline at end of file
diff --git a/40/CH8/EX8.16/Exa_8_16.jpg b/40/CH8/EX8.16/Exa_8_16.jpg
new file mode 100755
index 000000000..4a4bb37f1
--- /dev/null
+++ b/40/CH8/EX8.16/Exa_8_16.jpg
diff --git a/40/CH8/EX8.16/Exa_8_16.sce b/40/CH8/EX8.16/Exa_8_16.sce
new file mode 100755
index 000000000..4bd0eb54e
--- /dev/null
+++ b/40/CH8/EX8.16/Exa_8_16.sce
@@ -0,0 +1,12 @@
+//signal interpolation using FFT
+xn=[0 1 0 -1];
+XDFT=dft(xn,-1)
+ZT=[0 -2*%i 0 zeros(1:27) 0 2*%i];
+xn1=dft(ZT,1);
+t=0:1/length(xn1):1-(1/length(xn1));
+a=gca();
+a.x_location="origin";
+plot2d(t,xn1);
+xlabel('time t');
+ylabel('Amplitude');
+xtitle('Interpolated Sinusoid:4 samples over one period');
+\ No newline at end of file
diff --git a/40/CH8/EX8.17/Exa_8_17.sce b/40/CH8/EX8.17/Exa_8_17.sce
new file mode 100755
index 000000000..10f457b52
--- /dev/null
+++ b/40/CH8/EX8.17/Exa_8_17.sce
@@ -0,0 +1,8 @@
+//concept of periodogram
+xn=[0 1 0 -1];
+N=4;
+XDFT=dft(xn,-1);
+for i=1:length(XDFT)
+    p(i)=(1/N)*abs(XDFT(i)^2);
+end
+p//periodogram
+\ No newline at end of file
diff --git a/40/CH8/EX8.18/Exa_8_18.sce b/40/CH8/EX8.18/Exa_8_18.sce
new file mode 100755
index 000000000..c05785204
--- /dev/null
+++ b/40/CH8/EX8.18/Exa_8_18.sce
@@ -0,0 +1,9 @@
+//The DFT from the matrix formulation
+xn=[1;2;1;0];
+w=exp(-%i*%pi/2);
+for i=1:4
+    for j=1:4
+        WN(i,j)=w^((i-1)*(j-1));
+    end
+end
+XDFT=WN*xn
diff --git a/40/CH8/EX8.19/Exa_8_19.sce b/40/CH8/EX8.19/Exa_8_19.sce
new file mode 100755
index 000000000..77fcc0e9e
--- /dev/null
+++ b/40/CH8/EX8.19/Exa_8_19.sce
@@ -0,0 +1,10 @@
+//using DFT to find IDFT
+XDFT=[4;-2*%i;0;2*%i];
+XDFTc=[4;2*%i;0;-2*%i];
+w=exp(-%i*%pi/2);
+for i=1:4
+    for j=1:4
+        WN(i,j)=w^((i-1)*(j-1));
+    end
+end
+xn=1/4*(WN*XDFTc)
+\ No newline at end of file
diff --git a/40/CH8/EX8.2/Exa_8_2.sce b/40/CH8/EX8.2/Exa_8_2.sce
new file mode 100755
index 000000000..39450d7f1
--- /dev/null
+++ b/40/CH8/EX8.2/Exa_8_2.sce
@@ -0,0 +1,6 @@
+//The DTFT and conjugate symmetry
+//8-point DFT
+x=[1 1 0 0 0 0 0 0];
+XDFT=dft(x,-1);
+disp(XDFT,'The DFT of x is');
+disp('from conjugate symmetry we see XDFT[k]=XDFT[8-k]');
+\ No newline at end of file
diff --git a/40/CH8/EX8.20/Exa_8_20.sce b/40/CH8/EX8.20/Exa_8_20.sce
new file mode 100755
index 000000000..a87b49079
--- /dev/null
+++ b/40/CH8/EX8.20/Exa_8_20.sce
@@ -0,0 +1,9 @@
+//A four point decimation-in-frequency FFT algorithm
+x=[1 2 1 0];
+w=-%i;
+xdft(1)=x(1)+x(3)+x(2)+x(4);
+xdft(2)=x(1)-x(3)+w*(x(2)-x(4));
+xdft(3)=x(1)+x(3)-x(2)-x(4);
+xdft(4)=x(1)-x(3)-w*(x(2)-x(4));
+XDFT=dft(x,-1);
+xdft,XDFT
+\ No newline at end of file
diff --git a/40/CH8/EX8.21/Exa_8_21.sce b/40/CH8/EX8.21/Exa_8_21.sce
new file mode 100755
index 000000000..0014814a8
--- /dev/null
+++ b/40/CH8/EX8.21/Exa_8_21.sce
@@ -0,0 +1,11 @@
+//A four point decimation-in-time FFT algorithm
+x=[1 2 1 0];
+w=-%i;
+xdft=[0 0 0 0];
+for i=1:4
+    for j=1:4
+        xdft(i)=xdft(i)+x(j)*w^((i-1)*(j-1));
+    end
+end
+XDFT=dft(x,-1);
+xdft,XDFT
+\ No newline at end of file
diff --git a/40/CH8/EX8.22/Exa_8_22.sce b/40/CH8/EX8.22/Exa_8_22.sce
new file mode 100755
index 000000000..3cc472315
--- /dev/null
+++ b/40/CH8/EX8.22/Exa_8_22.sce
@@ -0,0 +1,9 @@
+//A 4-point DFT from a 3-point sequence
+xn=[1;2;1];
+w=exp(-%i*%pi/2);
+for i=1:4
+    for j=1:3
+        WN(i,j)=w^((i-1)*(j-1));
+    end
+end
+XDFT=WN*xn
+\ No newline at end of file
diff --git a/40/CH8/EX8.23/Exa_8_23.sce b/40/CH8/EX8.23/Exa_8_23.sce
new file mode 100755
index 000000000..4a6985f9e
--- /dev/null
+++ b/40/CH8/EX8.23/Exa_8_23.sce
@@ -0,0 +1,10 @@
+//A 3-point IDFT from 4-point DFT
+XDFT=[4;-2*%i;0;2*%i];
+w=exp(-%i*%pi/2);
+for i=1:4
+    for j=1:3
+        WN(i,j)=w^((i-1)*(j-1));
+    end
+end
+WI=WN';
+xn=1/4*(WI*XDFT)
+\ No newline at end of file
diff --git a/40/CH8/EX8.24/Exa_8_24.sce b/40/CH8/EX8.24/Exa_8_24.sce
new file mode 100755
index 000000000..5ad54e146
--- /dev/null
+++ b/40/CH8/EX8.24/Exa_8_24.sce
@@ -0,0 +1,24 @@
+//The importance of Periodic extension
+//(a)For M=3
+x=[1 2 1];
+XDFT=dft(x,-1)
+w=exp(-%i*2*%pi/3);
+for i=1:3
+    for j=1:3
+        WN(i,j)=w^((i-1)*(j-1));
+    end
+end
+WI=WN';
+xn=1/3*WI*XDFT
+//The result is periodic with M=3 & 1 period equals x[n]
+//(b)For M=4
+y=[1 2 1 0];
+YDFT=dft(y,-1)
+w=exp(-%i*%pi/2);
+for i=1:4
+    for j=1:4
+        WN(i,j)=w^((i-1)*(j-1));
+    end
+end
+WI=WN';
+yn=1/4*WI*YDFT
diff --git a/40/CH8/EX8.3/Exa_8_3.sce b/40/CH8/EX8.3/Exa_8_3.sce
new file mode 100755
index 000000000..fcf7eb76f
--- /dev/null
+++ b/40/CH8/EX8.3/Exa_8_3.sce
@@ -0,0 +1,24 @@
+//Circular shift and flipping
+//(a)right circular shift
+y=[1 2 3 4 5 0 0 6];
+f=y;g=y;h=y;
+for i=1:2
+    b=f(length(f));
+    for j=length(f):-1:2
+        f(j)=f(j-1);
+     end
+     f(1)=b;
+end
+disp(f,'By right circular shift y[n-2] is');
+//(b)left circular shift
+for i=1:2
+    a=g(1);
+    for j=1:length(g)-1
+        g(j)=g(j+1);
+     end
+     g(length(g))=a;
+end
+disp(g,'By left circular shift y[n+2] is');
+//(c)flipping property
+h=[h(1) h(length(h):-1:2)];
+disp(h,'By flipping property y[-n] is');
+\ No newline at end of file
diff --git a/40/CH8/EX8.4/Exa_8_4.sce b/40/CH8/EX8.4/Exa_8_4.sce
new file mode 100755
index 000000000..847b1bfa2
--- /dev/null
+++ b/40/CH8/EX8.4/Exa_8_4.sce
@@ -0,0 +1,21 @@
+x=[1 2 1 0];
+XDFT=dft(x,-1)
+//(a)time shift property
+y=x;
+for i=1:2
+    a=y(1);
+    for j=1:length(y)-1
+        y(j)=y(j+1);
+     end
+     y(length(y))=a;
+end
+YDFT=dft(y,-1)
+disp(YDFT,'By Time-Shift property DFT of x[n-2] is');  
+//(b)flipping property
+g=[x(1) x(length(x):-1:2)]
+GDFT=dft(g,-1)
+disp(GDFT,'By Time reversal property DFT of x[-n] is');  
+//(c)conjugation property
+p=XDFT;
+PDFT=[p(1);p(4:-1:2)];
+disp(YDFT,'BY conjugation property DFT of x*[n] is');  
diff --git a/40/CH8/EX8.5a/Exa_8_5a.sce b/40/CH8/EX8.5a/Exa_8_5a.sce
new file mode 100755
index 000000000..63e5aa5a4
--- /dev/null
+++ b/40/CH8/EX8.5a/Exa_8_5a.sce
@@ -0,0 +1,42 @@
+//properties of DFT
+//a1)product
+xn=[1 2 1 0];
+XDFT=dft(xn,-1)
+hn=xn.*xn
+HDFT=dft(hn,-1)
+HDFT1=1/4*(convol(XDFT,XDFT))
+HDFT1=[HDFT1,zeros(8:12)];
+HDFT2=[HDFT1(1:4);HDFT1(5:8);HDFT1(9:12)];
+HDFT3=[0 0 0 0];
+for i=1:4
+    for j=1:3
+        HDFT3(i)=HDFT3(i)+HDFT2(j,i);
+    end
+end
+disp(HDFT3,'DFT of x[n]^2 is');
+//a2)periodic convolution
+vn=convol(xn,xn);
+vn=[vn,zeros(8:12)];
+vn=[vn(1:4);vn(5:8);vn(9:12)];
+vn1=[0 0 0 0];
+for i=1:4
+    for j=1:3
+        vn1(i)=vn1(i)+vn(j,i);
+    end
+end
+VDFT=dft(vn1,-1);
+VDFT1=XDFT.*XDFT;
+disp(VDFT1,'DFT of x[n]*x[n] is');
+//a3)signal energy(parcewell's theorem)
+xn2=xn^2;
+E=0;
+for i=1:length(xn2)
+    E=E+abs(xn2(i));
+end
+XDFT2=XDFT^2
+E1=0;
+for i=1:length(XDFT2)
+    E1=E1+abs(XDFT2(i));
+end
+E,(1/4)*E1;
+disp(1/4*E1,'The energy of the signal is');
+\ No newline at end of file
diff --git a/40/CH8/EX8.5b/Exa_8_5b.sce b/40/CH8/EX8.5b/Exa_8_5b.sce
new file mode 100755
index 000000000..05c7e80c0
--- /dev/null
+++ b/40/CH8/EX8.5b/Exa_8_5b.sce
@@ -0,0 +1,42 @@
+//b1)modulation
+XDFT=[4 -2*%i 0 2*%i];
+xn=dft(XDFT,1)
+for i=1:length(xn)
+    zn(i)=xn(i)*%e^((%i*%pi*(i-1))/2);
+end
+disp(zn,'The IDFT of XDFT[k-1] is');
+ZDFT=[2*%i 4 -2*%i 0];
+zn1=dft(ZDFT,1)
+//b2)periodic convolution
+HDFT=(convol(XDFT,XDFT))
+HDFT=[HDFT,zeros(8:12)];
+HDFT=[HDFT(1:4);HDFT(5:8);HDFT(9:12)];
+HDFT1=[0 0 0 0];
+for i=1:4
+    for j=1:3
+        HDFT1(i)=HDFT1(i)+HDFT(j,i);
+    end
+end
+HDFT1;
+hn=dft(HDFT1,1)
+hn1=4*(xn.*xn);
+disp(hn1,'The IDFT of XDFT*XDFT is');
+//b3)product
+WDFT=XDFT.*XDFT;
+wn=dft(WDFT,1)
+wn1=convol(xn,xn);
+wn1=[wn1,zeros(8:12)];
+wn1=[wn1(1:4);wn1(5:8);wn1(9:12)];
+WN=[0 0 0 0];
+for i=1:4
+    for j=1:3
+        WN(i)=WN(i)+wn1(j,i);
+    end
+end
+disp(WN,'The IDFT of XDFT.XDFT is');
+//b4)Central ordinates and signal Energy
+E=0;
+for i=1:length(xn)
+    E=E+abs(xn(i)^2);
+end
+disp(E,'the signal energy is'); 
+\ No newline at end of file
diff --git a/40/CH8/EX8.5c/Exa_8_5c.sce b/40/CH8/EX8.5c/Exa_8_5c.sce
new file mode 100755
index 000000000..bc4c62f5d
--- /dev/null
+++ b/40/CH8/EX8.5c/Exa_8_5c.sce
@@ -0,0 +1,7 @@
+//Regular convolution
+xn=[1 2 1 0];
+yn=[1 2 1 0 0 0 0];
+YDFT=dft(yn,-1)
+SDFT=YDFT.*YDFT
+sn=dft(SDFT,1)
+sn1=convol(xn,xn)
+\ No newline at end of file
diff --git a/40/CH8/EX8.6/Exa_8_6.sce b/40/CH8/EX8.6/Exa_8_6.sce
new file mode 100755
index 000000000..be5c3cbb9
--- /dev/null
+++ b/40/CH8/EX8.6/Exa_8_6.sce
@@ -0,0 +1,20 @@
+//Signal and spectrum replication
+xn=[2 3 2 1];
+XDFT=dft(xn,-1)
+yn=[xn xn xn];
+YDFT=dft(yn,-1)
+YDFT1=3*[XDFT(1:1/3:length(XDFT))];
+for i=2:3
+    YDFT1(i:3:length(YDFT1))=0;
+end
+YDFT1(12:-1:11)=0;
+disp(YDFT1,'the DFT of x[n/3] is');
+hn=[xn(1:1/3:length(xn))]
+for i=2:3
+    hn(i:3:length(hn))=0;
+end
+hn(12:-1:11)=0;
+hn
+HDFT=dft(hn,-1)
+HDFT1=[XDFT;XDFT;XDFT];
+disp(HDFT1,'the DFT of y[n]=[x[n],x[n],x[n]] is');
+\ No newline at end of file
diff --git a/40/CH8/EX8.7/Exa_8_7.sce b/40/CH8/EX8.7/Exa_8_7.sce
new file mode 100755
index 000000000..9d9c9e16d
--- /dev/null
+++ b/40/CH8/EX8.7/Exa_8_7.sce
@@ -0,0 +1,7 @@
+//relating DFT and IDFT
+XDFT1=[4 -2*%i 0 2*%i];
+xn1=dft(XDFT1,1);
+disp(xn1,'The IDFT of XDFT1');
+XDFT2=[12 -24*%i 0 4*%e^(%i*%pi/4) 0 4*%e^(-%i*%pi/4) 0 24*%i];
+xn2=dft(XDFT2,1);
+disp(xn2,'The IDFT of XDFT1'); 
+\ No newline at end of file
diff --git a/40/CH8/EX8.8/Exa_8_8.sce b/40/CH8/EX8.8/Exa_8_8.sce
new file mode 100755
index 000000000..7fad7f114
--- /dev/null
+++ b/40/CH8/EX8.8/Exa_8_8.sce
@@ -0,0 +1,9 @@
+//Relating DFT and DTFT
+xn=[1 2 1 0];
+XDFT=dft(xn,-1);
+//for F=k/4,k=0,1,2,3
+for k=1:4
+    XF(k)=1+2*%e^(-%i*%pi*(k-1)/2)+%e^(-%i*%pi*(k-1));
+end
+XF,XDFT
+disp(XF,'The DFT of x[n] is');
diff --git a/40/CH8/EX8.9a/Exa_8_9a.sce b/40/CH8/EX8.9a/Exa_8_9a.sce
new file mode 100755
index 000000000..b61b2c4d9
--- /dev/null
+++ b/40/CH8/EX8.9a/Exa_8_9a.sce
@@ -0,0 +1,15 @@
+//DFT and DFS of sinusoids
+n2=0:0.5/1000:5.5/100;
+xt=4*cos(100*%pi*n2');
+n=0:(0.5)/100:(5.5)/100;//F=3/12 hence N=12
+xn=4*cos(100*%pi*n');
+XDFT=dft(xn,-1);
+n1=0:11;
+a=gca();
+a.x_location="origin";
+plot2d(n2,xt);
+plot2d3('gnn',n,xn);
+xset('window',1);
+b=gca();
+b.x_location="origin";
+plot2d3('gnn',n1,XDFT);
diff --git a/40/CH8/EX8.9a/Exa_8_9a_0.jpg b/40/CH8/EX8.9a/Exa_8_9a_0.jpg
new file mode 100755
index 000000000..7d2fad5b0
--- /dev/null
+++ b/40/CH8/EX8.9a/Exa_8_9a_0.jpg
diff --git a/40/CH8/EX8.9a/Exa_8_9a_1.jpg b/40/CH8/EX8.9a/Exa_8_9a_1.jpg
new file mode 100755
index 000000000..b0bd756d8
--- /dev/null
+++ b/40/CH8/EX8.9a/Exa_8_9a_1.jpg
diff --git a/40/CH8/EX8.9b/Exa_8_9b.sce b/40/CH8/EX8.9b/Exa_8_9b.sce
new file mode 100755
index 000000000..d32e7094c
--- /dev/null
+++ b/40/CH8/EX8.9b/Exa_8_9b.sce
@@ -0,0 +1,15 @@
+//DFT and DFS of sinusoids
+n2=0:1/1280:31/128;
+xt=4*sin(72*%pi*n2');
+n=0:1/128:31/128;//F=9/32 hence N=32
+xn=4*sin(72*%pi*n');
+XDFT=abs(dft(xn,-1));
+n1=0:31;
+a=gca();
+a.x_location="origin";
+plot2d(n2,xt);
+plot2d3('gnn',n,xn);
+xset('window',1);
+b=gca();
+b.x_location="origin";
+plot2d3('gnn',n1,XDFT);
diff --git a/40/CH8/EX8.9b/Exa_8_9b_0.jpg b/40/CH8/EX8.9b/Exa_8_9b_0.jpg
new file mode 100755
index 000000000..3ae80d7a6
--- /dev/null
+++ b/40/CH8/EX8.9b/Exa_8_9b_0.jpg
diff --git a/40/CH8/EX8.9b/Exa_8_9b_1.jpg b/40/CH8/EX8.9b/Exa_8_9b_1.jpg
new file mode 100755
index 000000000..e757639cc
--- /dev/null
+++ b/40/CH8/EX8.9b/Exa_8_9b_1.jpg
diff --git a/40/CH8/EX8.9c/Exa_8_9c.sce b/40/CH8/EX8.9c/Exa_8_9c.sce
new file mode 100755
index 000000000..67632bb96
--- /dev/null
+++ b/40/CH8/EX8.9c/Exa_8_9c.sce
@@ -0,0 +1,15 @@
+//DFT and DFS of sinusoids
+n2=0:1/840:6/21;
+xt=4*sin(72*%pi*n2')-6*cos(12*%pi*n2');
+n=0:1/21:6/21;//F=3/12 hence N=12
+xn=4*sin(72*%pi*n')-6*cos(12*%pi*n');
+XDFT=abs(dft(xn,-1));
+n1=0:6;
+a=gca();
+a.x_location="origin";
+plot2d(n2,xt);
+plot2d3('gnn',n,xn);
+xset('window',1);
+b=gca();
+b.x_location="origin";
+plot2d3('gnn',n1,XDFT);
diff --git a/40/CH8/EX8.9c/Exa_8_9c_0.jpg b/40/CH8/EX8.9c/Exa_8_9c_0.jpg
new file mode 100755
index 000000000..924bb1475
--- /dev/null
+++ b/40/CH8/EX8.9c/Exa_8_9c_0.jpg
diff --git a/40/CH8/EX8.9c/Exa_8_9c_1.jpg b/40/CH8/EX8.9c/Exa_8_9c_1.jpg
new file mode 100755
index 000000000..55efa132d
--- /dev/null
+++ b/40/CH8/EX8.9c/Exa_8_9c_1.jpg
diff --git a/40/CH8/EX8.9d/Exa_8_9d.sce b/40/CH8/EX8.9d/Exa_8_9d.sce
new file mode 100755
index 000000000..2d5d4b294
--- /dev/null
+++ b/40/CH8/EX8.9d/Exa_8_9d.sce
@@ -0,0 +1,15 @@
+//DFT and DFS of sinusoids
+n2=0:1/2400:23/240;
+xt=1+4*sin(120*%pi*n2')+4*sin(40*%pi*n2');
+n=0:1/240:23/240;//F=9/32 hence N=32
+xn=1+4*sin(120*%pi*n')+4*sin(40*%pi*n');
+XDFT=abs(dft(xn,-1));
+n1=0:23;
+a=gca();
+a.x_location="origin";
+plot2d(n2,xt);
+plot2d3('gnn',n,xn);
+xset('window',1);
+b=gca();
+b.x_location="origin";
+plot2d3('gnn',n1,XDFT);
+\ No newline at end of file
diff --git a/40/CH8/EX8.9d/Exa_8_9d_1.jpg b/40/CH8/EX8.9d/Exa_8_9d_1.jpg
new file mode 100755
index 000000000..baec0a646
--- /dev/null
+++ b/40/CH8/EX8.9d/Exa_8_9d_1.jpg
diff --git a/40/CH8/EX8.9d/exa_8_9d_0.jpg b/40/CH8/EX8.9d/exa_8_9d_0.jpg
new file mode 100755
index 000000000..2d0969b63
--- /dev/null
+++ b/40/CH8/EX8.9d/exa_8_9d_0.jpg
diff --git a/40/CH9/EX9.1/Exa_9_1.sce b/40/CH9/EX9.1/Exa_9_1.sce
new file mode 100755
index 000000000..44b5d2b9d
--- /dev/null
+++ b/40/CH9/EX9.1/Exa_9_1.sce
@@ -0,0 +1,53 @@
+//Response in variant mappings
+s=%s;z=%z;
+HS=1/(s+1);
+f=0:0.05:0.5;
+HS1=horner(HS,(%i*%pi*2*f'));
+ts=1;
+HZ=z/(z-0.3679);
+HZ1=horner(HZ,exp(%i*%pi*2*f'));
+a=gca();
+a.x_location="origin";
+subplot(211)
+plot2d(f,HS1);
+plot2d(f,HZ1);
+xlabel('Analog frequency f(Hz)');
+ylabel('Magnitude');
+xtitle('magnitude of H(s) and H(z)');
+HZ1=HZ1-0.582;//magnitude after gain matching at dc 
+b=gca();
+b.x_location="origin";
+subplot(212);
+plot2d(f,HS1);
+plot2d(f,HZ1);
+xlabel('Analog frequency f(Hz)');
+ylabel('Magnitude');
+xtitle('magnitude after gain matching at DC');
+//Impulse response of analog and digital filter
+t=0:0.01:6;
+ht=exp(-t');
+n=0:6;
+hn=exp(-n');
+xset('window',1)
+c=gca();
+subplot(211);
+plot2d(t,ht);
+plot2d3('gnn',n,hn);
+xlabel('DT index n and time t=nts');
+ylabel('Amplitude');
+xtitle('Impulse response of analog and digital filter');
+//Step response of analog and digital filter
+t=0:0.01:6;
+st=1-exp(-t');
+n=0:6;
+sn=(%e-%e^(-n'))/(%e-1);
+c=gca();
+subplot(212);
+plot2d(t,st);
+plot2d3('gnn',n,sn);
+xlabel('DT index n and time t=nts');
+ylabel('Amplitude');
+xtitle('Step response of analog and digital filter');
+
+
+
diff --git a/40/CH9/EX9.1/Exa_9_1_0.jpg b/40/CH9/EX9.1/Exa_9_1_0.jpg
new file mode 100755
index 000000000..4fa2975b5
--- /dev/null
+++ b/40/CH9/EX9.1/Exa_9_1_0.jpg
diff --git a/40/CH9/EX9.1/Exa_9_1_1.jpg b/40/CH9/EX9.1/Exa_9_1_1.jpg
new file mode 100755
index 000000000..a566f8d8e
--- /dev/null
+++ b/40/CH9/EX9.1/Exa_9_1_1.jpg
diff --git a/40/CH9/EX9.10a/Exa_9_10a.jpg b/40/CH9/EX9.10a/Exa_9_10a.jpg
new file mode 100755
index 000000000..5c242b942
--- /dev/null
+++ b/40/CH9/EX9.10a/Exa_9_10a.jpg
diff --git a/40/CH9/EX9.10a/Exa_9_10a.sce b/40/CH9/EX9.10a/Exa_9_10a.sce
new file mode 100755
index 000000000..3921304f2
--- /dev/null
+++ b/40/CH9/EX9.10a/Exa_9_10a.sce
@@ -0,0 +1,23 @@
+//Bilinear design of second order filters
+s=%s;z=%z;
+fo=6;Wo=2*%pi*fo/25;
+delf=5;S=25;
+B=cos(2*%pi*fo/25)
+C=tan(%pi*delf/25)
+HS=1/(s+1);
+HZ=horner(HS,(z^2-(2*B*z)+1)/(C*(z^2)-C))
+f=0:0.5:12.5;
+HZ1=horner(HZ,exp(%i*2*%pi*f'/25));
+HZ1=abs(HZ1);
+W2=(%pi*delf/25)+acos(cos(Wo)*cos(%pi*delf/25))
+W1=W2-(2*%pi*delf/25)
+f1=S*W1/(2*%pi),f2=S*W2/(2*%pi)
+f3=[f1;fo;f2];
+HZf=abs(horner(HZ,exp(%i*2*%pi*f3'/25)));
+a=gca();
+a.x_location="origin";
+plot2d(f,HZ1,rect=[0 0 13 1]);
+plot2d3('gnn',f3,HZf);
+xlabel('Analog Frequency f[kHZ]');
+ylabel('Magnitude');
+xtitle('Band pass filter fo=6kHZ,delf=5kHZ');
diff --git a/40/CH9/EX9.10b/Exa_9_10b.jpg b/40/CH9/EX9.10b/Exa_9_10b.jpg
new file mode 100755
index 000000000..b0abc6603
--- /dev/null
+++ b/40/CH9/EX9.10b/Exa_9_10b.jpg
diff --git a/40/CH9/EX9.10b/Exa_9_10b.sce b/40/CH9/EX9.10b/Exa_9_10b.sce
new file mode 100755
index 000000000..68eaef4a6
--- /dev/null
+++ b/40/CH9/EX9.10b/Exa_9_10b.sce
@@ -0,0 +1,21 @@
+//Bilinear design of second order filters
+s=%s;z=%z;
+f1=4;f2=9;
+delf=f2-f1;S=25;
+B=cos(%pi*(f1+f2)/25)/cos(%pi*(f2-f1)/25)
+C=tan(%pi*delf/25)
+HS=1/(s+1);
+HZ=horner(HS,(z^2-(2*B*z)+1)/(C*(z^2)-C))
+f=0:0.5:12.5;
+HZ1=horner(HZ,exp(%i*2*%pi*f'/25));
+HZ1=abs(HZ1);
+fo=S*acos(B)/(2*%pi)
+f3=[f1 fo f2]; 
+HZf=abs(horner(HZ,exp(-%i*2*%pi*f3'/25)));
+a=gca();
+a.x_location="origin";
+plot2d(f,HZ1);
+plot2d3('gnn',f3,HZf);
+xlabel('Analog Frequency f[kHZ]');
+ylabel('Magnitude');
+xtitle('Band pass filter f1=4kHZ,f2=9kHZ');
diff --git a/40/CH9/EX9.10c/Exa_9_10c.jpg b/40/CH9/EX9.10c/Exa_9_10c.jpg
new file mode 100755
index 000000000..c2434c961
--- /dev/null
+++ b/40/CH9/EX9.10c/Exa_9_10c.jpg
diff --git a/40/CH9/EX9.10c/Exa_9_10c.sce b/40/CH9/EX9.10c/Exa_9_10c.sce
new file mode 100755
index 000000000..ce7325884
--- /dev/null
+++ b/40/CH9/EX9.10c/Exa_9_10c.sce
@@ -0,0 +1,26 @@
+//Bilinear design of second order filters
+s=%s;z=%z;
+fo=40;Wo=2*%pi*fo/200;
+delf=2;S=25;
+delW=2*%pi*delf/200;
+B=cos(2*%pi*fo/200)
+K=0.557;
+C=K*tan(0.5*delW)
+HS=1/(s+1);
+HZ=horner(HS,(z^2-(2*B*z)+1)/(C*(z^2)-C))
+f=0:2:100;
+f1=35:0.5:45;
+HZ1=horner(HZ,exp(%i*2*%pi*f'/200));
+HZ2=horner(HZ,exp(%i*2*%pi*f1'/200));
+HZ1=abs(HZ1);
+HZ2=abs(HZ2);
+a=gca();
+a.x_location="origin";
+subplot(211);
+plot2d(f,HZ1);
+xlabel('Analog Frequency f[kHZ]');
+ylabel('Magnitude');
+xtitle('peaking filter fo=40HZ,delf=2HZ');
+subplot(212);
+plot2d(f1,HZ2);
+xtitle('Blowup of response 35HZ to 45HZ');
+\ No newline at end of file
diff --git a/40/CH9/EX9.11/Exa_9_11.jpg b/40/CH9/EX9.11/Exa_9_11.jpg
new file mode 100755
index 000000000..1a92d1260
--- /dev/null
+++ b/40/CH9/EX9.11/Exa_9_11.jpg
diff --git a/40/CH9/EX9.11/Exa_9_11.sce b/40/CH9/EX9.11/Exa_9_11.sce
new file mode 100755
index 000000000..35a2c585d
--- /dev/null
+++ b/40/CH9/EX9.11/Exa_9_11.sce
@@ -0,0 +1,30 @@
+//interference Rejection
+//design oh high-Q and low-Q notch filters
+s=%s;z=%z;
+Q=50;
+fo=60;S=300;
+delf=fo/Q;
+Wo=2*%pi*fo/S;
+delW=2*%pi*delf/S;
+C=tan(0.5*delW),B=cos(Wo)
+HS=(s)/(s+1);
+H1Z=horner(HS,(z^2-(2*B*z)+1)/(C*(z^2)-C))
+Q1=5;delf1=fo/Q1;
+delW1=2*%pi*delf1/S;
+C1=tan(0.5*delW1),B1=cos(Wo)
+H2Z=horner(HS,(z^2-(2*B1*z)+1)/(C1*(z^2)-C1))
+f=0:0.5:150;
+H1Z1=horner(H1Z,exp(%i*2*%pi*f'/S));
+H2Z1=horner(H2Z,exp(%i*2*%pi*f'/S));
+a=gca();
+subplot(211);
+plot2d(f,H1Z1);
+xlabel('Analog Frequency f[Hz]');
+ylabel('Magnitude');
+xtitle('60 HZ notch filter with Q=50');
+subplot(212);
+plot2d(f,H2Z1);
+xlabel('Analog Frequency f[Hz]');
+ylabel('Magnitude');
+xtitle('60 HZ notch filter with Q=5');
+
diff --git a/40/CH9/EX9.12/Exa_9_12.jpg b/40/CH9/EX9.12/Exa_9_12.jpg
new file mode 100755
index 000000000..8fe31f903
--- /dev/null
+++ b/40/CH9/EX9.12/Exa_9_12.jpg
diff --git a/40/CH9/EX9.12/Exa_9_12.sce b/40/CH9/EX9.12/Exa_9_12.sce
new file mode 100755
index 000000000..15b484acb
--- /dev/null
+++ b/40/CH9/EX9.12/Exa_9_12.sce
@@ -0,0 +1,36 @@
+//IIR filter design
+//Design of chebyshev IIR filter with following specifications
+fp1=1.6;fp2=1.8;fs1=3.2;fs2=4.8;//pass band edges
+Ap=2;As=20;S=12;
+s=%s;z=%z;
+//(a)Indirect Bilinear design
+W=2*%pi*[fp1 fp2 fs1 fs2]/S
+C=2;
+omega=2*tan(0.5*W');//prewarping each band edge frequency
+epsilon=sqrt(10^(0.1*Ap)-1);
+n=acosh(((10^(0.1*As)-1)/epsilon^2)^1/2)/(acosh(fs1/fp1));
+n=ceil(n)
+alpha=(1/n)*asinh(1/epsilon);
+for i=1:n
+    B(i)=(2*i-1)*%pi/(2*n);
+end
+for i=1:n
+    p(i)=-sinh(alpha)*sin(B(i))+%i*cosh(alpha)*cos(B(i));
+end
+Qs=1;
+for i=1:n
+    Qs=Qs*(s-p(i))
+end
+Qo=0.1634;
+HPS=Qo/Qs
+HBPS=horner(HPS,(s^2+1.5045^2)/(s*1.202))
+HZ=horner(HBPS,2*(z-1)/(z+1))
+f=0:0.001:0.5;
+HZF=abs(horner(HZ,exp(%i*2*%pi*f')));
+HBPF=abs(horner(HBPS,%i*2*%pi*f'));
+a=gca();
+plot2d(f,HZF);
+plot2d(f,HBPF);
+xlabel('Analog Frequency');
+ylabel('magnitude');
+xtitle('band pass filter designed by the bilinear transformation');
+\ No newline at end of file
diff --git a/40/CH9/EX9.2/Exa_9_2.sce b/40/CH9/EX9.2/Exa_9_2.sce
new file mode 100755
index 000000000..25164168a
--- /dev/null
+++ b/40/CH9/EX9.2/Exa_9_2.sce
@@ -0,0 +1,12 @@
+//Impulse invariant mappings
+//(a)converting H(s)=4s+7/s^2+5s+4 to H(z) using impulse invariance
+s=%s;
+z=%z;
+HS=(4*s+7)/(s^2+5*s+4);
+pfss(HS)
+ts=0.5;
+HZ=3*z/(z-%e^(-4*ts))+z/(z-%e^(-ts))
+//(b)converting H(s)=4s+7/s^2+5s+4 to H(z) using impulse invariance
+HS1=4/((s+1)*(s^2+4*s+5))
+pfss(HS1);
+HZ1=2*z/(z-%e^-ts)+(2*1.414*z^2*cos(-0.75*%pi)-2*1.414*(z/%e)*cos(0.5-0.75*%pi))/(z^2-2*(z/%e)*cos(0.5)+%e^-2)
diff --git a/40/CH9/EX9.3ab/Exa_9_3ab.jpg b/40/CH9/EX9.3ab/Exa_9_3ab.jpg
new file mode 100755
index 000000000..1c2c13a50
--- /dev/null
+++ b/40/CH9/EX9.3ab/Exa_9_3ab.jpg
diff --git a/40/CH9/EX9.3ab/Exa_9_3ab.sce b/40/CH9/EX9.3ab/Exa_9_3ab.sce
new file mode 100755
index 000000000..1ed9fffe0
--- /dev/null
+++ b/40/CH9/EX9.3ab/Exa_9_3ab.sce
@@ -0,0 +1,24 @@
+//(a)Impulse invariant design
+s=%s;z=%z;
+HS=1/(s+1);
+H1s=horner(HS,3*s/%pi)
+H1z=%pi/3*z/(z-%e^(-%pi/3))
+//Modified inmpulse invariant design
+HZ=z/(z-1/%e);
+HMZ=0.5*(z+1/%e)/(z-1/%e);//modified transfer function
+H1Z=HZ/horner(HZ,1)
+HM1Z=HMZ/horner(HMZ,1)
+f=0:0.05:0.5;
+HZ1=horner(HZ,exp(%i*2*%pi*f'));
+HMZ1=horner(HMZ,exp(%i*2*%pi*f'));
+H1Z1=horner(H1Z,exp(%i*2*%pi*f'));
+HM1Z1=horner(HM1Z,exp(%i*2*%pi*f'));
+a=gca();
+a.x_location="origin";
+plot2d(f,HZ1);
+plot2d(f,HMZ1);
+plot2d(f,H1Z1);
+plot2d(f,HM1Z1);
+xlabel('digital frequency');
+ylabel('Magnitude');
+xtitle('Impulse invariant design of H(s)=1/s+1 (dashed)');
+\ No newline at end of file
diff --git a/40/CH9/EX9.3cd/Exa_9_3cd.sce b/40/CH9/EX9.3cd/Exa_9_3cd.sce
new file mode 100755
index 000000000..ed81e1b28
--- /dev/null
+++ b/40/CH9/EX9.3cd/Exa_9_3cd.sce
@@ -0,0 +1,22 @@
+//modified Impulse invariant Design
+//(c)H(s)=4s+7/s^2+5s+4
+s=%s;z=%z;
+HS=(4*s+7)/(s^2+5*s+4);
+[d1]=degree(numer(HS));
+[d2]=degree(denom(HS));
+HZ=((3*z)/(z-%e^-2))+(z/(z-%e^-0.5))
+if (d2-d1==1) then
+    h=(4+7/%inf)/(1+5/%inf+4/%inf)
+    HMZ=HZ-0.5*h
+else
+    HMZ=HZ
+end
+HS1=4/((s+1)*(s^2+4*s+5))
+HZ1=(0.2146*z^2+0.093*z)/(z^3-1.2522*z^2+0.527*z-0.0821);
+[d1]=degree(numer(HS1));
+[d2]=degree(denom(HS1));
+if (d2-d1==1) then
+    HMZ1=HZ1-0.5*h
+else
+    HMZ1=HZ1
+end
diff --git a/40/CH9/EX9.5/Exa_9_5.sce b/40/CH9/EX9.5/Exa_9_5.sce
new file mode 100755
index 000000000..025deebe5
--- /dev/null
+++ b/40/CH9/EX9.5/Exa_9_5.sce
@@ -0,0 +1,12 @@
+//Mappings from difference algorithms
+//Backward difference mappings
+s=%s;z=%z;
+ts=1;a=1;
+HS=1/(s+a);
+HZa=horner(HS,(z-1)/(z*ts))
+z1=roots(denom(HZa))//for ts >0 HZa always stable
+HZb=horner(HS,(z-1)/ts)
+z2=roots(denom(HZb))//stable only for 0<ats<2
+HZc=horner(HS,(z^2-1)/(2*z*ts))
+z3=roots(denom(HZc))//magnitude of 1 pole is always>1 hence unstable
+
diff --git a/40/CH9/EX9.6/Exa_9_6.sce b/40/CH9/EX9.6/Exa_9_6.sce
new file mode 100755
index 000000000..eae65a968
--- /dev/null
+++ b/40/CH9/EX9.6/Exa_9_6.sce
@@ -0,0 +1,12 @@
+//Mappings from integration algorithm
+//(a)Trapezoidal integration algorithm
+s=%s;z=%z;
+a=input('enter the value of a')
+ts=input('enter the value of sampling time')
+HS=1/(s+1);
+HZa=horner(HS,2*(z-1)/(ts*(z+1)))
+za=roots(denom(HZa))//pole always less than 1 ,hence HZ is stable
+//(b)simphson's algorithm
+HZb=horner(HS,3*(z^2-1)/(ts*(z^2+4*z+1)))
+zb=roots(denom(HZb))
+//magnitude of 1 pole always greater than 1 ,hence HZ is unstable
+\ No newline at end of file
diff --git a/40/CH9/EX9.7/Exa_9_7.sce b/40/CH9/EX9.7/Exa_9_7.sce
new file mode 100755
index 000000000..a5b0811a4
--- /dev/null
+++ b/40/CH9/EX9.7/Exa_9_7.sce
@@ -0,0 +1,27 @@
+//DTFT of numerical algorithms
+//(a)For trapezoidal numerical integrator
+ieee(2)
+F=0:0.01:0.2;
+HTF=1/(%i*2*tan(%pi*F'));
+HIF=1/(%i*2*%pi*F');
+Ha=1-((%pi*F')^2)/3-((%pi*F')^4/45);
+//(b)For simphson's numerical integrator
+Hb=((2*%pi*F')).*((2+cos(2*%pi*F'))./(3*sin(2*%pi*F')));
+//For forward difference operator
+HFF=(%e^(%i*2*%pi*F'))-1;
+HDF=1/(%i*2*%pi*F');
+Hc=1+(%i*2*%pi*F')/2-(2*%pi*F')^2/6;
+Hc=abs(Hc);
+//for central difference operator
+HCF=sin(2*%pi*F')./(%i*4*%pi*%pi*F'^2);
+Hd=abs(sin(2*%pi*F')./(2*%pi*F'));
+length(F),length(Ha)
+a=gca();
+a.x_location="origin";
+plot2d(F,Ha,rect=[0,0.8,0.2,1.1]);
+plot2d(F,Hb);
+xtitle("Magnitude spectrum of Integration algorithms","Digital Frequency F","Magnitude");
+xset('window',1);
+plot2d(F,Hc,rect=[0,0.8,0.2,1.1]);
+plot2d(F,Hd);
+xtitle("Magnitude spectrum of difference algorithms","Digital Frequency F","Magnitude");
diff --git a/40/CH9/EX9.7/Exa_9_7_0.jpg b/40/CH9/EX9.7/Exa_9_7_0.jpg
new file mode 100755
index 000000000..cc6d890aa
--- /dev/null
+++ b/40/CH9/EX9.7/Exa_9_7_0.jpg
diff --git a/40/CH9/EX9.7/Exa_9_7_1.jpg b/40/CH9/EX9.7/Exa_9_7_1.jpg
new file mode 100755
index 000000000..c9fd88c2d
--- /dev/null
+++ b/40/CH9/EX9.7/Exa_9_7_1.jpg
diff --git a/40/CH9/EX9.8a/Exa_9_8a.jpg b/40/CH9/EX9.8a/Exa_9_8a.jpg
new file mode 100755
index 000000000..ea2d85852
--- /dev/null
+++ b/40/CH9/EX9.8a/Exa_9_8a.jpg
diff --git a/40/CH9/EX9.8a/Exa_9_8a.sce b/40/CH9/EX9.8a/Exa_9_8a.sce
new file mode 100755
index 000000000..b6864a0c4
--- /dev/null
+++ b/40/CH9/EX9.8a/Exa_9_8a.sce
@@ -0,0 +1,21 @@
+//Bilinear transformation
+//To convert bessel analog filter to digital filter
+s=%s;
+z=%z;
+HS=3/(s^2+3*s+3);
+Wa=4;//analog omega
+Wd=%pi/2;//digital omega
+T=(2/Wa)*(tan(Wd/2));
+HZ=horner(HS,(2/T)*(z-1)/(z+1))
+f=0:0.1:6;
+HS1=horner(HS,(%i*4*f'/3));
+HS1=abs(HS1);
+HZ1=horner(HZ,exp(-%i*%pi*f'/6));
+HZ1=abs(HZ1);
+a=gca();
+a.x_location="origin";
+plot2d(f,HS1);
+plot2d(f,HZ1);
+xlabel('Analog Frequency f[kHZ)');
+ylabel('Magnitude');
+xtitle('Bessel filter H(s) and digital filter H(z)');
+\ No newline at end of file
diff --git a/40/CH9/EX9.8b/Exa_9_8b.jpg b/40/CH9/EX9.8b/Exa_9_8b.jpg
new file mode 100755
index 000000000..e99357100
--- /dev/null
+++ b/40/CH9/EX9.8b/Exa_9_8b.jpg
diff --git a/40/CH9/EX9.8b/Exa_9_8b.sce b/40/CH9/EX9.8b/Exa_9_8b.sce
new file mode 100755
index 000000000..fc27bc3d6
--- /dev/null
+++ b/40/CH9/EX9.8b/Exa_9_8b.sce
@@ -0,0 +1,20 @@
+//Bilinear transformation
+//To convert twin-T notch analog filter to digital filter
+s=%s;
+z=%z;
+HS=(s^2+1)/(s^2+4*s+1);
+Wo=1;
+S=240;f=60;//sampling and analog frequencies
+W=0.5*%pi;//digital frequency
+C=Wo/tan(0.5*W)
+HZ=horner(HS,C*(z-1)/(z+1))
+f=0:120;
+HZ1=abs(horner(HZ,exp(-%i*%pi*f'/120)));
+HS1=abs(horner(HS,(%i*f'/60)));
+a=gca();
+a.x_location="origin";
+plot2d(f,HZ1);
+plot2d(f,HS1);
+xlabel('Analog Frequency f[kHZ]');
+ylabel('Magnitude');
+xtitle('Notch filter H(S) and digital filter H(z)');
diff --git a/40/CH9/EX9.9/Exa_9_9.jpg b/40/CH9/EX9.9/Exa_9_9.jpg
new file mode 100755
index 000000000..a8c62febf
--- /dev/null
+++ b/40/CH9/EX9.9/Exa_9_9.jpg
diff --git a/40/CH9/EX9.9/Exa_9_9.sce b/40/CH9/EX9.9/Exa_9_9.sce
new file mode 100755
index 000000000..6551c31ad
--- /dev/null
+++ b/40/CH9/EX9.9/Exa_9_9.sce
@@ -0,0 +1,37 @@
+//D2D transformations
+//(a)LP 2 HP transformation
+z=%z;
+HZ=(3*(z+1)^2)/(31*z^2-26*z+7);
+WD=0.5*%pi;WC=0.25*%pi;//Band edges
+a=-cos(0.5*(WD+WC))/cos(0.5*(WD-WC))//Mapping parameter
+HHPZ=horner(HZ,-(z+a)/(1+a*z))
+//(b)LP 2 BP transformation
+W1=0.25*%pi;
+W2=0.75*%pi;
+K=tan(0.5*WD)/tan(0.5*(W2-W1))
+a=-cos(0.5*(W1+W2))/cos(0.5*(W1-W2))//Mapping parameters k,a,A1,A2
+A1=2*K*a/(K+1),A2=(K-1)/(K+1)
+HBPZ=horner(HZ,-(z^2+A1*z+A2)/(A2*z^2+A1*z+1))
+//(c)Lp 2 BS transformation
+w1=3/8*%pi;w2=5/8*%pi;//band edges
+K1=tan(0.5*WD)*tan(0.5*(w2-w1))
+a1=-cos(0.5*(w1+w2))/cos(0.5*(w2-w1))//Mapping parameters k1,a1,A1c,A2c
+A1c=2*a1/(K1+1),A2c=-(K1-1)/(K1+1)
+HBSZ=horner(HZ,(z^2+A1c*z+A2c)/(A2c*z^2+A1c*z+1))
+f=0:1/256:4;
+for i=1:length(f)
+HZ1(i)=horner(HZ,exp(-%i*%pi*f(i)/4));
+end
+HZ1=abs(HZ1);
+HHPZ1=abs(horner(HHPZ,exp(-%i*%pi*f'/4)));
+HBPZ1=abs(horner(HBPZ,exp(-%i*%pi*f'/4)));
+HBSZ1=abs(horner(HBSZ,exp(-%i*%pi*f'/4)));
+a=gca();
+a.x_location="origin";
+plot2d(f,HZ1);
+plot2d(f,HHPZ1);
+plot2d(f,HBPZ1);
+plot2d(f,HBSZ1);
+xlabel('Analog Frequency');
+ylabel('Magnitude');
+xtitle('Digital-to-digital transformations of a low pass filter');
+\ No newline at end of file
diff --git a/40/DEPENDENCIES/Aliasfrequency.sci b/40/DEPENDENCIES/Aliasfrequency.sci
new file mode 100755
index 000000000..1fcc781bf
--- /dev/null
+++ b/40/DEPENDENCIES/Aliasfrequency.sci
@@ -0,0 +1,15 @@
+function[F]=aliasfrequency(f,s,s1)
+if (s>2*f) then
+    disp("alias has not occured")
+else
+    disp("alias has occured")
+end
+F=f/s;
+for i=1:100
+    if (abs(F)>0.5)
+        F=F-i;
+    end
+end
+fa=F*s1;
+disp(fa,"frequency of reconstructed signal is")
+endfunction
+\ No newline at end of file