2013/01/17 by Fabian Schuh, Schuh, Fabian, Andreas Schenk +3
Computer Science · Mathematics · #FOS: Computer and information sciences #Information Theory (cs.IT) #cs.IT #math.IT
paper · pdf · doi:10.48550/arxiv.1301.4050
5 pages, 10 figures, submitted to IEEE International Symposium on Information Theory 2013 (ISIT)
arxiv created 2013/01/17 · arxiv updated 2013/01/18
In classic trellis-coded modulation (TCM) signal constellations of twice the cardinality are applied when compared to an uncoded transmission enabling transmission of one bit of redundancy per PAM-symbol, i.e., rates of (K)/(K+1) when 2K+1 denotes the cardinality of the signal constellation. In order to support different rates, multi-dimensional (i.e., D-dimensional) constellations had been proposed by means of combining subsequent one- or two-dimensional modulation steps, resulting in TCM-schemes with (1)/(D) bit redundancy per real dimension. In contrast, in this paper we propose to perform rate adjustment for TCM by means of puncturing the convolutional code (CC) on which a TCM-scheme is based on. It is shown, that due to the nontrivial mapping of the output symbols of the CC to signal points in the case of puncturing, a modification of the corresponding Viterbi-decoder algorithm and an optimization of the CC and the puncturing scheme are necessary.