A new concept of Bit Geometrical Uniformity and its application to BICM-ID systems

A new concept of bit geometrical uniformity (BGU) is introduced to help the analysis and estimation of performance of systems with iterative detection/decoding (ID). It is also shown that the BGU labelings of the signal constellation allows a fast search for best component binary recursive systematic convolutional (RSC) codes of a BICM-ID system using both of overall and in-line interleaving. Best rate-1/2 RSC codes are reported for 4PSK constellation as an example. The new concept and new search method can be directly extended to MPSK and MQAM constellations.