Performance Comparison of Iterative BP and Threshold Decoding for Convolutional Self-Doubly-Orthogonal Codes

The forward-only iterative decoding techniques for convolutional self-doubly-orthogonal codes are systematically presented based on one-step belief propagation (BP) decoding and one-step threshold decoding. A feedback mechanism and a weighing technique are examined in order to improve both the convergence speed and error performance. Computer simulation results show that compared with the iterative threshold decoding over an additive white Gaussian noise channel, the iterative BP decoding for these codes achieves essentially the same error performance while requiring only about half the number of iterations. Therefore, these two iterative decoding techniques can provide a tradeoff between the latency and the complexity of decoding and allow for the applications of these codes in very high speed wireless communications.