Forced Convergence Decoding of LDPC Codes - EXIT Chart Analysis and Combination with Node Complexity Reduction Techniques

Recently, the concept of forced convergence decoding for Low-Density Parity-Check Codes has been introduced. Restricting the message passing in the iterative process to the nodes that still significantly contribute to the decoding result, this approach allows for substantial reduction in decoding complexity at negligible deterioration in performance. We analyze this novel technique using EXIT charts and show how it compares to and can be combined with other complexity reduction techniques. Our findings imply that forced convergence works effectively in conjunction with other complexity reduction techniques while retaining its attractiveness in terms of the complexity-performance trade-off.

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