Performance Analysis of BITCM System with Specified Bandwidth Efficiency

In this paper, performances of BITCM system are analyzed in AWGN and Rayleigh channels. The bandwidth efficiency is specified as 2 bit/s/Hz and 3 bit/s/Hz, and different tradeoffs are made between code rate and modulation constellation in BITCM transmitter. Monte Carlo simulation results indicate that the BITCM systems with same bandwidth efficiency perform diversely. In AWGN channel, it has better BER performance with smaller constellation size, but in Rayleigh channel, with lower code rate, it has shown greater anti-fading and anti-noise capability. An explanation is given for that and general principles are proposed as to how to choose an appropriate combination scheme of code rate and modulation constellation in BITCM system under different channel conditions.