Improving LDPC decoding performance for ATSC 3.0 LDM profiles

ATSC 3.0 includes Layered Division Multiplexing (LDM) in addition to the traditional Time Division Multiplexing (TDM) technique in order to offer simultaneous stationary and mobile services. At the receiver side, Log-likelihood ratio (LLR) probability density functions are considered in the decoding process. The main objective of this paper is to analyze the performance of using different LLR PDF formulas for LDM signals in order to find the best trade-off between performance and implementation requirements, measuring the performance gain over TDM.