8.Calculation of receiver antenna gain

1. Antenna diameter   Diameter of parabolic reflector antenna is referred as antenna diameter. It is denoted by ‘D.

2.Antenna efficiency   Antenna efficiency is the ratio of input power to the radiated power of the antenna. It is denoted by ‘h’. The value of ‘h’ lice between 0.55 to 0.73.

3.Antenna gain G_R   The isotropic power gain of the antenna, G_T, is defined as the power density in the maximum direction, denoted here by P_{D ,}to the power density archived by a 100% efficient isotropic radiator.
             Thus
                                             G_R=P_D/(P_T/4p)
                           P_Tis the total power radiated.
            Antenna gain in G_R (dB) = 10 log (p²D²h(l²*100))
                                                   = 10 log (p²D²h/((C/f)²*100))
                                                   =10 log (p²D²h/((3/10*f)²*100))
                                                    =10 log (p²D²h/(3/f)²)……(dB)……………[12]