A novel waveform for FQPSK modulation

Feher Quadrature Phase Shift Keying (FQPSK) is a quasi constant envelope modulation and it can be used to improve the power efficiency of high power amplifier (HPA). However, the envelope of FQPSK still has a least fluctuation of 0.18dB and can be further improved. New waveforms for FQPSK modulation are presented in this paper. The performance of the FQPSK adopting new waveform is justified by analysis and simulation. The signal of new FQPSK has the strictly constant envelope. It improves the power efficiency of the amplifiers to the utmost, and outperforms over conventional FQPSK in both the bandwidth efficiency and the end to end performance of bit error probability. At last, the impact of frequency selective multi-path fading on the bit error rate performance of new FQPSK is derived and analyzed.