Evaluation of bit error rate and optimization of error correcting capability assignment for a diversity system with multilevel coding over a fading channel

Abstract

In a fading channel without ISI, the approximate theoretical BER for a diversity reception system where multilevel coding is applied has been determined. The result obtained from the approximate theoretical BER method matches the simulation result, and thus this method can be used as an alternative for evaluating a coding system through simulation. Using the approximate theoretical BER method with a BCH code of length 31 and a rate of 63/93, the optimum error correcting capability assignments at BER = 10−6 for two and three branches have been determined. The error capability assignments (3, 2, 1), (5, 1, 1) have been found to be optimum for levels 1, 2, 3 of the block code, respectively. In the case of a channel with M intersymbol interference, it has been shown that the BER for a given SNR = η [dB] of an interleaving, adaptive equalization, multilevel coding combination system can be estimated using the approximate theoretical BER of an (M + 1) branch diversity whose SNR is η − 10 log10( M + 1) [dB] . © 1999 Scripta Technica, Electron Comm Jpn Pt 3, 82(6): 26–35, 1999