Soft Metrics and EXIT Chart Analysis of Noncoherent MFSK with Diversity Reception in Rician Fading Channel

Abstract

A convolutionally encoded noncoherent M-ary Frequency Shift Keying (MFSK) modulation scheme with diversity reception is considered. Soft metrics for Soft Decision Decoding (SDD) of noncoherent MFSK are derived assuming Rician channel model. Furthermore, the convergence behavior of the MFSK receiver is investigated using EXtrinsic Information Transfer (EXIT) charts. It has been demonstrated that the derived expressions for soft information are useful allowing SDD of the MFSK scheme exploiting diversity and the EXIT chart analysis provides useful insights into its iterative decoding behavior.