Abstract: Architecture for enhancing the encoding/decoding of information of a channel. A stream of incoming information bits are arranged into a first array of information bits. The first array of information bits are processed into a first code of bits, which bits form a plurality of first code words having a minimum distance to neighboring error events. Selected bits of the first code are rearranged into a second array of bits by intermittent successive rotations of the selected bits of the first code. A second code is then generated from the second array of bits to increase the minimum distance to the neighboring error events.

Abstract: The optimum decoding of component codes in Block Coded Modulation (BCM) schemes requires the use of the Log-Likelihood Ratio (LLR) as the signal metric. The essence of the invention is a means of accurately approximating the computation of the LLR in a way which is simple to implement directly. The invention, the Log-Likelihood Ratio Planar Approximation (LLRPA), mathematically consists solely of planar equations with fixed point arithmetic that provides both an accurate estimate of the LLR and is easily realized in electronic hardware.