Evaluation of a Joint Detector Demodulator Decoder (JDDD) Performance With Modulation Schemes Specified in the DVB-S2 Standard

Abstract

With the rapid increase in the growth of digital broadcast technologies, there has been a demand for high data rate, power, and bandwidth efficient transmission, which, today, is aided by the high-performing low-density parity check (LDPC) codes. In this paper, we explore a novel alternative scheme to the LDPC decoder that performs detection, demodulation, and decoding jointly, coined the joint detector demodulator decoder (JDDD). We test the JDDD through simulation using the modulation schemes defined in the DVB-S2 satellite broadcasting standard. The JDDD is a more recently developed algorithm to the sum-product algorithm (SPA) that is used in decoding the LDPC codes. The JDDD is optimal over a modulated additive white Gaussian noise/intersymbol interference (ISI) channel when resources are sufficient, with the main constraint limiting the algorithm being the availability of computing resources. In this paper, we compare the performance of the system using the JDDD against that of the LDPC decoder. The main result is that the JDDD is able to outperform the iterative detector decoder (IDD) at shorter codeword lengths, when resource requirement is smaller, while the increase in computational requirements tends to favor the IDD at longer CWLs.