A Design of Differentially Encoded LDPC Coding Based on Multi-Edge Framework

We propose to optimize the design of a system of which the transmitter is composed of a low-density parity-check (LDPC) code followed by differential encoding (DE). The DE is included to remove the phase ambiguity in channel estimates. To achieve low complexity and/or high efficiency in channel estimation and also an acceptable performance in transmission, we optimize the outer LDPC code by considering the DE-LDPC code as a multi-edge type LDPC (MET-LDPC) code. The advantage of the proposed approach is verified by both the asymptotic behaviour and the finite-length simulation.