On Power Spectrum Optimization of M-ary Position PSK Modulations

Aimed at the discrete components affecting power spectrum sideband level, the spectral properties of the M-ary Position Phase Shift Keying (MPPSK) modulated signal is derived. The waveform optimization and full M-ary position is proposed to suppress these discrete spectral components. Two demodulators to adapt the optimized MPPSK signals are designed and simulated. The theoretical analysis and experimental results show that the discrete components are greatly suppressed with these two methods and the spectrum utilization is enhanced, the -40 dB bandwidth is tightened up by a factor of 73.72% and 43.72% respectively. 0.3~0.7 dB in signal to noise ratio at the same bit error rate is saved for waveform optimization demodulation than for full M-ary position demodulation which demonstrates the feasibility and validity of these two methods.