Simulation of a high frequency satellite link with a fade countermeasure

A DSP simulator of a full duplex high frequency satellite link with a generalized fade countermeasure has been presented. By feeding synthesized stochastic/dynamic rain attenuation and amplitude scintillation time-series into detailed power link budget equations, it is possible to simulate the expected carrier/noise ratio variations on either forward or return channels. Due to frequency scaling, these will in general be different even on a symmetrical VSAT network. The proposed fading simulator can mimic most known characteristics such as geographical diversity, instantaneous frequency scaling and hysteresis for rain attenuation. The communication channel simulator can match, in the long run, the expected long-term power spectral density and first order statistics as predicted from models. It is also emphasized that the use of a generalized fade countermeasure results in a very substantial improvement in user data throughput allowing operation close to channel capacity.