| Since the invention of Trellis-Coded Modulation (TCM) in 1982 by Gottfried Ungerboeck it has been known that significant gains can be achieved by jointly designing coding and modulation. This paper presents a comparison of the current modulation schemes used with Low-Density Parity-Check (LDPC) codes, and introduces a new coded modulation scheme for LDPC codes entitled Reliability-Based Coded Modulation (RBCM). This new method can improve Bit Error Rate (BER) performance of regular LDPC codes for non-binary modulation schemes by 0.2 to 0.6 dB, with little or no added complexity. |
