mGainoverTemperature.m

%Example 4.3.4 
%Statement: An earth station antenna has a diameter of 30m with an overall
%efficiency of 68% and is used to reveice a signal at 4150 MHz. At this
%frequency, the system noise temperature is 79 K when the antenna points at
%the satellite at an elevation angle of 28 degrees. What is the Earth
%Station G/T ratio under these conditions. If the sky temperature rises due
%to heavy rain to 88 K. 

%% Parameters
Aeff=68/100; % Aperture antenna efficiciency 
D=30; %Diameter of the antenna in meters
Ts1=79; %Mean system noise temperature 
Ts2=88; %System noise temperature under heavy rain
c=2.99e8; %speed of light
f=4150e6; % downlink operational frequency of the Earth Station
lambda=c/f; %wavelength of the downlink operational frequency


%% Gain over temperature
Gr=Aeff*(pi*D/lambda)^2; % Gain of the receiving antenna for a circular aperture
GrdB=10*log10(Gr); % Gain in dB
TsdB=10*log10(Ts1); % Mean system noise temperature in dB
GoverT=GrdB-TsdB; % Gain over Temperature at average conditions (dB/K)
Ts2dB=10*log10(Ts2); % System noise temperature in dB under heavy rain conditions
GoverT2=GrdB-Ts2dB; % Gain over Temperature under heavy rain conditions (dB/K)