8 files changed, 152 insertions, 0 deletions
diff --git a/1655/CH8/EX7.q/Question_7.sce b/1655/CH8/EX7.q/Question_7.sce
new file mode 100755
index 000000000..5b6220afb
--- /dev/null
+++ b/1655/CH8/EX7.q/Question_7.sce
@@ -0,0 +1,16 @@
+// Question 7  page 8.55
+
+clc;
+clear;
+
+w=25d-6;    //width
+v=3d4;      //velocity
+
+t=w/v;      //computing drift time
+BW=(2*%pi*t)^-1;        //computing bandwidth
+rt=1/BW;    //response time
+rt=rt*10^9;
+
+printf("\nMaximum response time is %.2f ns.",rt);
+
+//Answer in the book is given as 5.24ns deviation of 0.01ns
diff --git a/1655/CH8/EX8.10.1/Example_8_10_1.sce b/1655/CH8/EX8.10.1/Example_8_10_1.sce
new file mode 100755
index 000000000..54baf9931
--- /dev/null
+++ b/1655/CH8/EX8.10.1/Example_8_10_1.sce
@@ -0,0 +1,11 @@
+// Example 8.10.1  page 8.25
+
+clc;
+clear;
+
+//erfc 4.24 is given to be 2d-9
+
+SN=(2*sqrt(2)*4.24)^2;  //computing optical SNR
+SN=round(SN);
+SN1=sqrt(SN);       //computing electrical SNR
+printf("\nOptical SNR is %d.\nElectrical SNR is %d.",SN,SN1);
diff --git a/1655/CH8/EX8.11.1/Example_8_11_1.sce b/1655/CH8/EX8.11.1/Example_8_11_1.sce
new file mode 100755
index 000000000..a3c7c21a3
--- /dev/null
+++ b/1655/CH8/EX8.11.1/Example_8_11_1.sce
@@ -0,0 +1,10 @@
+// Example 8.11.1  page 8.26
+
+clc;
+clear;
+
+P=1d-9;     //probability of error
+eta=1;
+N= -log(P);
+N1=round(N);
+printf("Thus %.1f or %d photons are required for maintaining 10^-9 BER.\nAssuming eta=1;\nE=%.1f*hv.",N,N1,N);
diff --git a/1655/CH8/EX8.17.1/Example_8_17_1.sce b/1655/CH8/EX8.17.1/Example_8_17_1.sce
new file mode 100755
index 000000000..46245f5f9
--- /dev/null
+++ b/1655/CH8/EX8.17.1/Example_8_17_1.sce
@@ -0,0 +1,27 @@
+// Example 8.17.1  page 8.46
+
+clc;
+clear;
+
+lamda=0.85d-6;
+h=6.626d-34;    //plank's constant
+c=3d8;      //speed of light
+q=1.6d-19;  //charge of electron
+eta=65/100; //quantum efficiency
+P0=300d-9;  //optical power
+Id=3.5;    //dark current
+B=6.5d6;     //bandwidth
+K=1.39d-23; //Boltzman constant
+T=293;      //temperature
+R=5d3;     //load resister
+Ip= 10^9*eta*P0*q*lamda/(h*c);
+Its=10^9*(2*q*B*(Ip+Id));
+Its=sqrt(Its);
+printf("\nrms shot noise current is %.2f nA.",Its);
+
+It= 4*K*T*B/R;
+It=sqrt(It);
+It=It*10^9;
+printf("\nThermal noise is %.2f nA.",It);
+
+//answer given in book for Thermal noise it is 4.58nA, deviation is 0.02nA.
diff --git a/1655/CH8/EX8.17.2/Example_8_17_2.sce b/1655/CH8/EX8.17.2/Example_8_17_2.sce
new file mode 100755
index 000000000..96b0d84dd
--- /dev/null
+++ b/1655/CH8/EX8.17.2/Example_8_17_2.sce
@@ -0,0 +1,30 @@
+// Example 8.17.2  page 8.47
+
+clc;
+clear;
+
+lamda=0.85d-6;
+h=6.626d-34;    //plank's constant
+c=3d8;      //speed of light
+q=1.6d-19;  //charge of electron
+eta=65/100; //quantum efficiency
+P0=300d-9;  //optical power
+Id=3.5;    //dark current
+B=6.5d6;     //bandwidth
+K=1.39d-23; //Boltzman constant
+T=293;      //temperature
+R=5d3;     //load resister
+F_dB=3;     //noise figure
+F=10^(F_dB/10);
+Ip=10^9*eta*P0*q*lamda/(h*c);
+Its=10^9*(2*q*B*(Ip+Id));
+It1= 4*K*T*B*F/R;
+
+SN= Ip^2/(Its+It1);
+SN_dB=10*log10(SN);
+SN=SN/10^4;
+
+printf("\nSNR is %.2f*10^4 or %.2f dB.",SN,SN_dB);
+
+//answer given in the book is 6.16*10^4 (deviation of 0.9) and 47.8dB (deviation of 0.16dB)
+
diff --git a/1655/CH8/EX8.18.1/Example_8_18_1.sce b/1655/CH8/EX8.18.1/Example_8_18_1.sce
new file mode 100755
index 000000000..2cde55eb7
--- /dev/null
+++ b/1655/CH8/EX8.18.1/Example_8_18_1.sce
@@ -0,0 +1,16 @@
+// Example 8.18.1  page 8.48
+
+clc;
+clear;
+
+Cd=7d-12;
+B=9d6;
+Ca=7d-12;
+
+R=(2*3.14*Cd*B)^-1;
+B1=(2*3.14*R*(Cd+Ca))^-1;
+R=R/1000;
+B1=B1/10^6;
+printf("\nThus for 9MHz bandwidth maximum load resistance is %.2f Kohm\nNow if we consider input capacitance of following amplifier Ca then Bandwidth is %.2fMHz\nMaximum post detection bandwidth is half.",R,B1);
+
+//answer for resistance in the book is 4.51Kohm, deviation of 0.01Kohm, while for bandwidth it is 4.51 MHz, deviation of 0.01MHz
diff --git a/1655/CH8/EX8.3.1/Example_8_3_1.sce b/1655/CH8/EX8.3.1/Example_8_3_1.sce
new file mode 100755
index 000000000..c8a4d9ff7
--- /dev/null
+++ b/1655/CH8/EX8.3.1/Example_8_3_1.sce
@@ -0,0 +1,20 @@
+// Example 8.3.1  page 8.9
+
+clc;
+clear;
+
+P=10^-9;    //probability of error
+eta=1;      //ideal detector
+h=6.626d-34 //plank's constant
+c=3d8;     //speed of light
+lamda=1d-6; //wavelength
+B=10^7;     //bit rate
+
+Mn= - log(P);
+printf("\n The quantum imit at the receiver to maintain bit error rate 10^-9 is (%.1f*h*f)/eta.",Mn);
+f=c/lamda
+Popt= 0.5*Mn*h*f*B/eta;     //computing optical power
+Popt_dB = 10 * log10(Popt) + 30;    //optical power in dbm
+Popt=Popt*10^12;
+
+printf("\nMinimum incident optical power is %.1f W or %.1f dBm.",Popt,Popt_dB);
diff --git a/1655/CH8/EX8.3.2/Example_8_3_2.sce b/1655/CH8/EX8.3.2/Example_8_3_2.sce
new file mode 100755
index 000000000..2450424e1
--- /dev/null
+++ b/1655/CH8/EX8.3.2/Example_8_3_2.sce
@@ -0,0 +1,22 @@
+// Example 8.3.2  page 8.11
+
+clc;
+clear;
+
+SN_dB=60;    //signal to noise ratio
+h=6.626d-34 //plank's constant
+c=3d8;     //speed of light
+lamda=1.3d-6; //wavelength
+eta=1;
+B=6.5d6;     //Bandwidth
+
+SN=10^(SN_dB/10);
+f=c/lamda
+Popt= 2*SN*h*f*B/eta;     //computing optical power
+Popt_dB = 10 * log10(Popt) + 30;    //optical power in dbm
+Popt=Popt*10^6;
+printf("\nIncident power required to get an SNR of 60 dB at the receiver is %.4f microWatt or %.3f dBm",Popt,Popt_dB);
+printf("\nNOTE - Calculation error in the book.\nThey have take SN as 10^5 while calculating, which has lead to an error in final answer");
+
+//Calculation error in the book.They have take SN as 10^5 while calculating, which has lead to an error in final answer
+//answer in the book 198.1nW and -37.71 dBm