Effect of transmitter filter on the performance of FSK‐DPD and DPSK‐DPD in satellite mobile channel

Abstract

We study the effect of bandlimiting transmitter filter on the bit error probability (BEP) of M‐ary Frequency Shift Keying and Differential Phase Shift Keying with Differential Phase Detector in Satellite Mobile Channel. Numerical results are presented in the case when the transmitter and receiver filters are Butterworth filters of order NT = 4 and NR = 3 respectively. The BEP is reduced with increasing transmitter bandwidth with a minimum at infinite bandwidth, i.e. no transmitter filter. However finite values of this bandwidth can be used without significantly increasing the BEP. In the computation of the BEP we optimised various parameters, like the receiver bandwidth, sampling time, modulation index (for FSK only) and decision level.