LLR-based Erasure Decoding of SFH-MFSK in the presence of tone jamming

Error and Erasure decoding (E²D) is known to yield better performance than error-only decoding. Therefore, Erasure insertion (EI) has been applied to noncoherent M-ary frequency shift keying (MFSK) with slow frequency hopping (SFH) and Reed Solomon (RS) coding, when the system operates in the presence of jamming and fading. In this context, various criteria have been proposed to declare erasures in MFSK. One of these criteria is the Ratio Threshold Test (RTT). In this contribution, we employ symbol probabilities based RTT as an EI criteria i.e. an erasure is declared when ratio of the second largest to the largest symbol probabilities exceed a given threshold. Through simulation results we demonstrate that this scheme outperforms the conventional RTT in terms of combating tone jamming (MTJ) and Nakagami-m fading.