PERFORMANCE IMPROVEMENT IN WCDMA SYSTEM SUBJECTED TO INCREASED DATA RATE AND INTERFERENCE CHANNELS USING COMPENSATION FOR ERRORS

Abstract

Most mobile operators have rolled out third generation (3G) networks which have more benefits compared to first and second generation networks since it can support voice, data and multimedia applications. The rise in demand  for integrated services (capacity) has led to  interchannel  and  inter-symbol  interference among  the users and on transmission the signal is degraded again due to interference channels along the path. The digital signal  processing  techniques are applied in third  generation  (3G) mobile  communication systems to  reduce interference and power consumption. The main objective is to develop wideband code division multiple access (WCDMA) system model  whose  performance  has  been  improved  by  applying compensation for errors. Thismodel is subjected to an interference channels and data rate increased from 64kbps to 2Mbps. The computer simulation  tool  (Matlab 7.8) is  used to  develop and evaluate  the bit  error  rate  (BER) performance of  the system. The model  is  developed  in Simulink which has  blocks in  the  communication  blockset  which  have parameters for  simulation  of  the system. The bit  error rate (BERs) is calculated  at  the receiver with/without compensation of errors. For a data rate of 2Mbps, the average error rate is 0.4817 with error correction and 0.5165 without correction in an additive white Gaussian channel (AWGN).  In conclusion, the performance of the WCDMA model improves by 6.74% at 2Mbps, 5.59% at 384kbps, 5.79% at 144kbps and 5.32% 64kbps. This shows that the performance of the system improves by using this method when the data rate is increased in an additive white Gaussian channel. It also performs better at higher rates than in lower rates.

Key words: Bit error rate, interference channels, Third generation (3G), wideband code division multiple access