Performance of Turbo Coded Wireless Link for SIMO Using SC EGC and MRC

In this paper, performance of a Turbo coded wireless link is evaluated in the presence of Rayleigh fading for single transmit antenna and multiple receive antennas system using selective combining, equal gain combing and maximal ratio combining. Data are encoded using turbo encoder then modulated by QPSK or 16 QAM or 64 QAM before transmitting. And at the receiver combination is performed by using selective combing, equal gain combing and maximal ratio combining. It is observed that the turbo coded system with 2, 4, 6 and 8 receive antennas using selective combining provide 35, 28, 24 and 24 dB coding gain respectively, turbo coded system with 2, 4, 6 and 8 receive antennas using equal gain combining provide 34, 22, 20 and 19 dB coding gain respectively and turbo coded system with 2, 4, 6 and 8 receive antennas using maximal ratio combining provide 27, 17, 15 and 13 dB coding gain respectively at a BER 10-6. It is also observed that turbo coded system using maximal ratio combining provides 20 to 26 dB coding gain at a BER of 10-6 compared to turbo coded system using equal gain combining. And turbo coded system using maximal ratio combining provides 23 to 26 dB coding gain at a BER of 10-6 compared to turbo coded system using selective combining.