EXIT Chart Aided Design of Near-Capacity Self-Concatenated Trellis Coded Modulation Using Iterative Decoding

Abstract

In this contribution we design the Iteratively Decoded Self-Concatenated Convolutional Codes (SECCC-ID) using extrinsic information transfer (EXIT) charts. Good constituent Trellis Coded Modulation (TCM) codes are selected for communicating over both uncorrelated Rayleigh fading and Additive White Gaussian Noise (AWGN) channels. At the receiver iterative decoding is invoked for exchanging extrinsic information between the hypothetical decoder components. The convergence behaviour of the decoder is analysed with the aid of symbol-based EXIT charts. Similarly, the search for the best TCM constituent codes is also based on EXIT chart analysis. Finally, we demonstrate that the selected codes are capable of operating within 1 dB from the maximum achievable rate.