Performance analysis of a simo wireless link with turbo coding

Abstract

Performance analysis is carried out for a wireless communication system with single transmitter and multiple receiving antenna diversity over a Rayleigh fading channel with Turbo error correction coding. The analysis includes the development of bit error rate (BER) expression analytically considering different types of Turbo codes. Performance results are evaluated in terms of bit error rate (BER) as a function of signal to noise ratio (SNR) for different system parameters like number of receiving antenna, fading parameters and doppler frequency shift along with different free distance of the code. It is found that there are significant improvement in receiver performance over Rayleigh fading channel due to incorporation of Turbo coding in the presence of receive diversity with maximum ratio combining. The improvement occurs in terms of lowering of the BER floor which can not be lowered even by increasing number of receiving antenna. Order of improvement in BER floor is around 10-3 to 10-6. Further there are improvement in receiver performance in terms of coding gain. At a given BER, 10-3, the amount of coding gain is found to be 2 dB to 20 dB depending on the value of the system parameters and the free distance of the code. It is also noticed that coding gain is higher when the dopploer shift frequency is more and free distance of the code is higher and less no of antenna. The results will find application in the design of SIMO wireless communication System with Turbo coding.