Hardware evaluation of PSK modem through non-linear satellite channel

Two modulation schemes and three filter configurations are evaluated through the Intelsat-V satellite channel simulator using a TDMA modem. It is shown that the conventional quadrature phase shift-keying modulation scheme is superior to the offset-quadrature variant both in terms of BER and carrier and clock recovery performance. It is also demonstrated that the filter configuration using a square root Nyquist filter in conjunction with an aperture equalizer for the receiver filter provides a better performance than the configurations using a full Nyquist shaping on the transmit side.