summaryrefslogtreecommitdiff
path: root/2219/CH7
diff options
context:
space:
mode:
Diffstat (limited to '2219/CH7')
-rwxr-xr-x2219/CH7/EX7.1/Ex7_1.sce17
-rwxr-xr-x2219/CH7/EX7.10/Ex7_10.sce32
-rwxr-xr-x2219/CH7/EX7.11/Ex7_11.sce17
-rwxr-xr-x2219/CH7/EX7.12/Ex7_12.sce13
-rwxr-xr-x2219/CH7/EX7.13/Ex7_13.sce22
-rwxr-xr-x2219/CH7/EX7.14/Ex7_14.sce18
-rwxr-xr-x2219/CH7/EX7.15/Ex7_15.sce13
-rwxr-xr-x2219/CH7/EX7.16/Ex7_16.sce19
-rwxr-xr-x2219/CH7/EX7.17/Ex7_17.sce24
-rwxr-xr-x2219/CH7/EX7.18/Ex7_18.sce24
-rwxr-xr-x2219/CH7/EX7.19/Ex7_19.sce19
-rwxr-xr-x2219/CH7/EX7.2/Ex7_2.sce17
-rwxr-xr-x2219/CH7/EX7.3/Ex7_3.sce20
-rwxr-xr-x2219/CH7/EX7.4/Ex7_4.sce16
-rwxr-xr-x2219/CH7/EX7.5/Ex7_5.sce14
-rwxr-xr-x2219/CH7/EX7.6/Ex7_6.sce25
-rwxr-xr-x2219/CH7/EX7.7/Ex7_7.sce11
-rwxr-xr-x2219/CH7/EX7.8/Ex7_8.sce29
-rwxr-xr-x2219/CH7/EX7.9/Ex7_9.sce13
19 files changed, 363 insertions, 0 deletions
diff --git a/2219/CH7/EX7.1/Ex7_1.sce b/2219/CH7/EX7.1/Ex7_1.sce
new file mode 100755
index 000000000..ad9312af4
--- /dev/null
+++ b/2219/CH7/EX7.1/Ex7_1.sce
@@ -0,0 +1,17 @@
+// chapter 7 example 1
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+Ldipole = 50; // Length of dipole in cm
+c = 3*10^10; // velocity of EM wave in cm/s
+BW = 10*10^6; // bandwidth in Hz
+
+// Calculations
+lamda = 2*Ldipole; // wavelength in cm
+fo = c/lamda; // operating frequency in Hz
+Q = fo/BW // quality factor
+
+// Output
+mprintf('Q = %d',Q);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.10/Ex7_10.sce b/2219/CH7/EX7.10/Ex7_10.sce
new file mode 100755
index 000000000..8c746e512
--- /dev/null
+++ b/2219/CH7/EX7.10/Ex7_10.sce
@@ -0,0 +1,32 @@
+// chapter 7 example 10
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+RSSR = 20; // Rx signal strength in horizontal polarised antenna when rx RHCP
+
+// Calculations
+// When incident polarisation is circularly polarised and the antenna is linearly polarised,there is a ploarisation loss of 3dB
+ISS = RSSR + 3;
+// a
+// when the Rx polarisation is same as the antenna polarisation , the polarisation loss is zero
+RSS_HP = ISS; // rx signal strength for incident wave horizontally polarised
+// b
+// when the incident wave is vertically polarised ,the angle between the incident polarisation and the antenna polarisation is 90
+// polarisation loss = 20log(1/cos( φ))
+// = 20log(1/cos90) = ∞
+RSS_VP = 0; // rx signal strength for incident wave vertically polarised
+// c
+// When the incident wave is LHCP and the antenna polarisation is linear ,there will be a 3dB polarisation loss and the
+// Rx signal strength therefore will be 20 dB only
+RSS_LHCP = RSSR; // rx signal strength for incident wave Left hand circularly polarised
+// d
+// The angle between the incident wave polarisation and the antenna polarisation is 60 degrees
+phi = 60; // rx wave polarisation angle with horizontal
+PL = 20*log10(1/cos(60*%pi/180)); // polarisation loss in dB
+RSS_Pangle = ISS - PL;
+//output
+mprintf('Received signal strength if incident wave horizontally polarised = %d dB\n Received signal strength if incident wave vertically polarised = %d dB\n Received signal strength if incident wave Left hand circularly polarised is %d dB\n Received signal strength if Received wave polarisation making 60deg angle with horizontal is %3.0f dB',RSS_HP,RSS_VP,RSS_LHCP,RSS_Pangle);
+//--------------------------------------------------------------------------------
+
+
diff --git a/2219/CH7/EX7.11/Ex7_11.sce b/2219/CH7/EX7.11/Ex7_11.sce
new file mode 100755
index 000000000..d51eaac64
--- /dev/null
+++ b/2219/CH7/EX7.11/Ex7_11.sce
@@ -0,0 +1,17 @@
+// chapter 7 example 11
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+f = 300*10^6; // operating frequency in Hz
+c = 3*10^10; // velocity of EM wave in cm/s
+
+// Calculations
+lamda = c/f; // wavelength in cm
+// Physical length of antenna is made 5% shorter than desired length as per rule of thumb
+l = lamda/2; // length of halfwave dipole
+lphy = l-(5/100)*l; // as per rule of thumb
+
+// Output
+mprintf('Length of a half wave dipole to be cut = %3.1f cm',lphy);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.12/Ex7_12.sce b/2219/CH7/EX7.12/Ex7_12.sce
new file mode 100755
index 000000000..a66c753de
--- /dev/null
+++ b/2219/CH7/EX7.12/Ex7_12.sce
@@ -0,0 +1,13 @@
+// chapter 7 example 12
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+Zi = 72; // input impedance in ohms
+// A = 1.5a // area of cross section in sq.cm
+// Zif = Zi*[(sum of areas of cross section of various components)/(Area of cross section of the driven element )]^2
+// Zif = 72*((a + 1.5a)/a)^2;
+// Zif = 72*(2.5*a/a)^2;
+Zif = 72*(2.5)^2;
+mprintf('Input impedance for a folded dipole = %d Ω',Zif);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.13/Ex7_13.sce b/2219/CH7/EX7.13/Ex7_13.sce
new file mode 100755
index 000000000..8cd772783
--- /dev/null
+++ b/2219/CH7/EX7.13/Ex7_13.sce
@@ -0,0 +1,22 @@
+// chapter 7 example 13
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+f = 60*10^6; // frequency in Hz
+c = 3*10^8 // velocity of EM wave in m/s
+
+// Calculations
+lamda = c/f; // wavelength in m
+l_dipole= lamda/2 // length of diplole
+// Physical length of antenna is made 5% shorter than desired length as per rule of thumb
+L = l_dipole - (5/100)*l_dipole; // actual physical length
+L_D = L - (4/100)*L; // length of director
+L_R = L + (4/100)*L; // length of reflector
+DDS = 0.12*lamda; // director dipole spacing
+RDS = 0.2*lamda; // Reflector dipole spacing
+
+// Output
+mprintf('Length of dipole = %3.3f m\n length of Director = %3.2f m\n length of Reflector = %3.2f m\n director dipole spacing = %3.1f m\n Reflector dipole spacing = %3.1f m',L,L_D,L_R,DDS,RDS);
+//------------------------------------------------------------------------------
+
diff --git a/2219/CH7/EX7.14/Ex7_14.sce b/2219/CH7/EX7.14/Ex7_14.sce
new file mode 100755
index 000000000..6148ff0df
--- /dev/null
+++ b/2219/CH7/EX7.14/Ex7_14.sce
@@ -0,0 +1,18 @@
+// chapter 7 example 14
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+D = 2; // Mouth diameter in m
+f = 2; // focal length in m
+bw3db = 90/100; // beamwidth of antenna chosen to be 90% of angle subtended by feed
+
+// Calculations
+theta = 4*atan(1/(4*f/D)); // angle subtended by the focal point feed at edges of reflector
+theta_d = theta*180/%pi
+Beam_w_3dB = bw3db*theta_d; // 3 dB beam width
+NNBW = 2*(Beam_w_3dB );
+
+// Output
+mprintf('3 dB Beamwidth = %3.1f°\n Null-to-Null beam width = %3.2f°\n',Beam_w_3dB,NNBW);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.15/Ex7_15.sce b/2219/CH7/EX7.15/Ex7_15.sce
new file mode 100755
index 000000000..b611f05d3
--- /dev/null
+++ b/2219/CH7/EX7.15/Ex7_15.sce
@@ -0,0 +1,13 @@
+// chapter 7 example 15
+//-----------------------------------------------------------------------------
+clc;
+clear;
+f = 3; // focal length in m
+fpos = 1.5; // feed is placed 1.5m from pt of intersection os sec.reflector and antenna axis
+
+// Calculation
+f_hyp = f-fpos; // focal length of hyperboloid from figure;
+
+// Output
+mprintf('focal length of hyperboloid = %3.1f m',f_hyp);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.16/Ex7_16.sce b/2219/CH7/EX7.16/Ex7_16.sce
new file mode 100755
index 000000000..e5c811dab
--- /dev/null
+++ b/2219/CH7/EX7.16/Ex7_16.sce
@@ -0,0 +1,19 @@
+// chapter 7 example 16
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+D = 3; // Mouth diameter in m
+//f = 2; // focal length in m
+bw3db = 63; // 3dB beam width
+k = 0.9; // beam width is k times subtended angle
+
+// Calculations
+theta = bw3db/k; // subtended angle
+theta_r = theta
+//theta = 4*atan(1/(4*f/D));
+f = D/(4*tan((theta_r/4)*(%pi/180)));
+
+// Output
+mprintf('Distance of feed from the point of intersection of antenna axis and the reflector surface = %3.2f m',f);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.17/Ex7_17.sce b/2219/CH7/EX7.17/Ex7_17.sce
new file mode 100755
index 000000000..058eb4d2d
--- /dev/null
+++ b/2219/CH7/EX7.17/Ex7_17.sce
@@ -0,0 +1,24 @@
+// chapter 7 example 17
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+c = 3*10^8; // velocity of EM waves in m/s
+f = 2.5*10^9; // operating frequency in Ghz
+S = 10*10^-2; // inter element spacing
+theta = 10; // steering angle
+
+// Calculations
+lamda = c/f // Wavelength in m
+phi = (360*(S/lamda))*sin(theta*(%pi/180))
+phi1 = 0*phi // phase angle for element 1
+phi2 = 1*phi // phase angle for element 2
+phi3 = 2*phi // phase angle for element 3
+phi4 = 3*phi // phase angle for element 4
+phi5 = 4*phi // phase angle for element 5
+
+// Output
+mprintf('Phase angles for elements 1,2,3,4,5 are %d°, %d°, %d°, %d°, %d°',phi1,phi2,phi3,phi4,phi5);
+//------------------------------------------------------------------------------
+
+
diff --git a/2219/CH7/EX7.18/Ex7_18.sce b/2219/CH7/EX7.18/Ex7_18.sce
new file mode 100755
index 000000000..5b8c13b31
--- /dev/null
+++ b/2219/CH7/EX7.18/Ex7_18.sce
@@ -0,0 +1,24 @@
+// chapter 7 example 17
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// Data is taken from Example 17. The beam steers towards left of the axis with all parameters remaining in Ex 17 are same
+c = 3*10^8; // velocity of EM waves in m/s
+f = 2.5*10^9; // operating frequency in Ghz
+S = 10*10^-2; // inter element spacing
+theta = -10; // steering angle
+
+// Calculations
+lamda = c/f // Wavelength in m
+phi = (360*S/lamda)*sin(theta*%pi/180)
+phi1 = 0*phi // phase angle for element 1
+phi2 = 1*phi // phase angle for element 2
+phi3 = 2*phi // phase angle for element 3
+phi4 = 3*phi // phase angle for element 4
+phi5 = 4*phi // phase angle for element 5
+
+// Output
+mprintf('Phase angles for elements 1,2,3,4,5 are %d°, %d°, %d°, %d°, %d°',phi1,phi2,phi3,phi4,phi5);
+//------------------------------------------------------------------------------
+
+
diff --git a/2219/CH7/EX7.19/Ex7_19.sce b/2219/CH7/EX7.19/Ex7_19.sce
new file mode 100755
index 000000000..841a21e91
--- /dev/null
+++ b/2219/CH7/EX7.19/Ex7_19.sce
@@ -0,0 +1,19 @@
+// chapter 7 example 8
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+S = 5*10^-2; // inter spacing distance
+lamda = 6*10^-2; // operating wavelength in cms
+phi_Az = 25 // angle in azimuth direction
+phi_E = 35 // angle in Elevation direction
+
+// Calculations
+theta_Az = asin((lamda*phi_Az)/(360*S))
+theta_E = asin((lamda*phi_E)/(360*S))
+Theta_Az = theta_Az*(180/%pi)
+Theta_E = theta_E*(180/%pi)
+
+// Output
+mprintf('Steering angle in Azimuth = %3.1f°\n Steering angle in Elevation = %3.1f°',Theta_Az,Theta_E);
+//-----------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.2/Ex7_2.sce b/2219/CH7/EX7.2/Ex7_2.sce
new file mode 100755
index 000000000..3a8f569d5
--- /dev/null
+++ b/2219/CH7/EX7.2/Ex7_2.sce
@@ -0,0 +1,17 @@
+// chapter 7 example 2
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+Rr = 72; // Radiation resistance in ohms
+Rl = 8; // Loss resistance in ohms
+Ap = 27; // power gain
+
+// Calculations
+n = Rr/(Rr + Rl); // radiation efficiency
+D = Ap/n; // Directivity
+D_dB = 10*log10(D); // directivity in dB
+
+// Output
+mprintf('Directivity = %3.2f dB',D_dB );
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.3/Ex7_3.sce b/2219/CH7/EX7.3/Ex7_3.sce
new file mode 100755
index 000000000..e33421759
--- /dev/null
+++ b/2219/CH7/EX7.3/Ex7_3.sce
@@ -0,0 +1,20 @@
+// chapter 7 example 3
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+AZ_BW = 0.5; // beamwidth in degrees
+E_BW = 0.5; // beamwidth in degrees
+lamda = 3*10^-2; // radar emission wavelength
+
+// Calculations
+
+AZ_BW_r = AZ_BW*%pi/180; // azimuth beamwidth in radians
+E_BW_r = E_BW*%pi/180; // elevation beamwidth in radians
+G = (4*%pi)/(AZ_BW_r *E_BW_r ) // antenna gain
+G_db = 10*log10(G) // gain in dB
+A = (G*lamda*lamda)/(4*%pi); // antenna aperture
+
+// Output
+mprintf('Gain of Antenna = %3.2f dB\n Antenna Aperture = %3.3f m',G_db,A);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.4/Ex7_4.sce b/2219/CH7/EX7.4/Ex7_4.sce
new file mode 100755
index 000000000..23712c3f0
--- /dev/null
+++ b/2219/CH7/EX7.4/Ex7_4.sce
@@ -0,0 +1,16 @@
+// chapter 7 example 4
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+n_az = 0.5; //length efficiency in azimuth direction
+n_el = 0.7; //length efficiency in elevation direction
+A = 10; // area in square mts
+
+// Calculations
+n = n_az * n_el; // aperture efficiency
+Ae = n*A; // Effective aperture
+
+// Output
+mprintf('Effective aperture of the antenna = %3.1f sq.m',Ae);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.5/Ex7_5.sce b/2219/CH7/EX7.5/Ex7_5.sce
new file mode 100755
index 000000000..8c042dcdd
--- /dev/null
+++ b/2219/CH7/EX7.5/Ex7_5.sce
@@ -0,0 +1,14 @@
+// chapter 7 example 5
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+Ptot = 100; // certain antenna radiating power
+Ptot_iso = 10*10^3; // isotropic antenna radiating power
+
+// Calculations
+D = 10*log10(Ptot_iso/Ptot); // Directivity of antenna
+
+// Output
+mprintf('Directivity of antenna = %d dB',D);
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.6/Ex7_6.sce b/2219/CH7/EX7.6/Ex7_6.sce
new file mode 100755
index 000000000..9487ac5fb
--- /dev/null
+++ b/2219/CH7/EX7.6/Ex7_6.sce
@@ -0,0 +1,25 @@
+// chapter 7 example 6
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+D = 3; // diameter of the antenna in m
+n_l = 0.7; // length efficiency
+nr = 0.9; // radiation efficiency
+f = 10*10^9; // antenna operating freq.
+c = 3*10^8; // vel of EM waves in m/s
+
+// calculations
+def = D*n_l // Effective diameter
+lamda = c/f // wavelength in m
+Beam_w = lamda/def // beamwidth in radian
+Beam_w_d= Beam_w*180/%pi; // beam width in degree;
+n_a = n_l * n_l; // Aperture efficiency
+AA = (%pi*D*D)/4; // actual area in sq m
+Ae = AA*n_a; // Effective aperture
+G = (4*%pi*Ae)/(lamda^2); // Gain
+G_db = 10*log10(G);
+
+// Output
+mprintf('Beam Width = %3.2f degrees\n Effective Aperture = %3.2fsq m\n Gain = %3.1f dB',Beam_w_d,Ae,G_db);
+//-------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.7/Ex7_7.sce b/2219/CH7/EX7.7/Ex7_7.sce
new file mode 100755
index 000000000..6ef19c66f
--- /dev/null
+++ b/2219/CH7/EX7.7/Ex7_7.sce
@@ -0,0 +1,11 @@
+// chapter 7 example 7
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+// given (lamda/10) wire dipole
+// Radiation resistance of short dipoles is Rr = 790*(1/lamda)^2;
+// Rr = 790*(lamda/(10*lamda))^2;
+// Rr = 7.9;
+mprintf('Radiation resistance = 7.9 ohms');
+//------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.8/Ex7_8.sce b/2219/CH7/EX7.8/Ex7_8.sce
new file mode 100755
index 000000000..bd4dabfed
--- /dev/null
+++ b/2219/CH7/EX7.8/Ex7_8.sce
@@ -0,0 +1,29 @@
+// chapter 7 example 8
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+a_l = 6; // Azimuth length in m
+n_a = 0.7; // Azimuth length efficiency
+n_e = 0.5; // elevation length efficiency
+e_l = 4; // elevation length in m
+w = 6; // width of antenna
+h = 4; // height of antenna
+lamda = 3*10^-2; // wavelength
+
+// Calculations
+Eff_A_l = a_l*n_a; // effective azimuth length
+Eff_E_l = e_l*n_e; // effective elevation length
+A = w*h // actual area
+n = n_a*n_e; // aperture efficiency
+Ae = A*n; // effective aperture
+Az_BW = lamda/Eff_A_l // Azimuth beam width
+E_BW = lamda/Eff_E_l // elevation beam width
+Az_BW_d = Az_BW*180/%pi // rad to deg conv
+E_BW_d = E_BW*180/%pi; // rad to deg conv
+G = (4*%pi*Ae)/(lamda^2); //Gain
+G_dB = 10*log10(G); // gain in dB
+
+// Output
+mprintf('Azimuth Beamwidth = %3.2f degrees\n Elevation Beamwidth = %3.2f degrees\n Gain = %3.1f dB',Az_BW_d,E_BW_d,G_dB);
+//-------------------------------------------------------------------------------
diff --git a/2219/CH7/EX7.9/Ex7_9.sce b/2219/CH7/EX7.9/Ex7_9.sce
new file mode 100755
index 000000000..99bea2c42
--- /dev/null
+++ b/2219/CH7/EX7.9/Ex7_9.sce
@@ -0,0 +1,13 @@
+// chapter 7 example 9
+//-----------------------------------------------------------------------------
+clc;
+clear;
+// given data
+Beam_w_3db = 0.4;
+
+// Calculations
+N2N_Beam_w = 2*Beam_w_3db; // Null to Null beamwidth
+
+// output
+mprintf('Null to Null Beam width = %3.1f degrees',N2N_Beam_w);
+//------------------------------------------------------------------------------
generated by cgit (git 2.34.1) at 2024-12-20 17:46:31 +0000