Multiple symbol differential detection of MDPSK in narrowband interference and AWGN

In this paper, we propose a new technique for rejection of narrowband interference based on multiple symbol detection of differential phase shift keying (PSK). Our proposed technique employs a special signalling or vector coding scheme which is shown to be optimum against narrowband interference under certain conditions. As an example of application, we apply our proposed technique to a SFH/DPSK system which is suitable for high speed spread spectrum communications such as a wireless LAN (local area network). Its BER (bit error rate) performance in both narrowband interference and AWGN (additive white Gaussian noise) which may model the background noise is evaluated. We show that even in the worst case narrowband interference, our proposed technique can offer a significant gain in the power ratio of signal to narrowband interference