MATLAB Listing

%Figure 2.10(a); ‘Mobile satellite communication; Principles and trends’ by M.Richharia;

%Equation (2.13) of ‘Satellite Communication System:Design Principles by M.Richharia;

%Semimajor axis versus rate of change of argument of perigee;

%Matlab source code writeen by AR/MR;Year 2000, V 1.0;

%wdotc = 4.97*(R./a).^3.5*(5*(cos (i*pi/180))^2-1)/(1-e^2)^2;

%where, wdotc = Rate of change of argument of perigee;R = mean equatorial radius (6378 Km)

%a = semi-major axis; i = inclination; e = eccentricity;

R=6378; %Mean equatorial radius;

a=linspace(6378+500,15000+6378,1000);%semi major axis;

figure(‘color’,’white’);

hold;

i = 45;% inclination;

e = 0.1; % eccentricity;

wdota=4.97*(R./a).^3.5*(5*(cos (i*pi/180))^2-1)/(1-e^2)^2;     

i = 90;% inclination;

e = 0.1; % eccentricity;

wdotb=4.97*(R./a).^3.5*(5*(cos (i*pi/180))^2-1)/(1-e^2)^2;

i = 5;% inclination;

e = 0.1; % eccentricity;

wdotc=4.97*(R./a).^3.5*(5*(cos (i*pi/180))^2-1)/(1-e^2)^2;      

i = 63.4;% inclination;

e = 0.1; % eccentricity;

wdotd=4.97*(R./a).^3.5*(5*(cos (i*pi/180))^2-1)/(1-e^2)^2;

%Plot figure;

plot(a,wdota,’k’,a,wdotb,’k’,a,wdotc,’k’,a,wdotd,’k’)

%legend(‘i=45′,’i=90′,’i=5′,’i=63.4’)

axis([700+6378 15000+6378 -inf inf]);

xlabel(‘Semi-major axis (Km)’);

ylabel(‘Rate of change of argument of perigee (deg/day)’);

grid on;

zoom;