BER Performance of Space-Time Coded MMSE DFE for Wideband Code Division Multiple Access (WCDMA)

Sanjay Kumar SHARMA, S. Naseem AHMAD

Dept. of Electronics and Communication Engg, Jamia Millia Islamia, Delhi, India.
Dept. of Electronics and Communication Engg., Krishna Institute of Engg. and Technology, Ghaziabad, India.

DOI: 10.4236/ijcns.2009.24030                

Abstract

In recent times, there has been growing interests in integration of voice, data and video traffic in wireless communication networks. With these growing interests, WCDMA has immerged as an attractive access technique. The performance of WCDMA system is deteriorated in presence of multipath fading environment. The paper presents space-time coded minimum mean square error (MMSE) Decision Feedback Equalizer (DFE) for wideband code division multiple access (WCDMA) in a frequency selective channel. The filter coefficients in MMSE DFE are optimized to suppress noise, intersymbol interference (ISI), and multiple access interference (MAI) with reasonable system complexity. For the above structure, we have presented the estimation of BER for a MMSE DFE using computer simulation experiments. The simulation includes the effects of additive white Gaussian noise, multipath fading and multiple access interference (MAI). Furthermore, the performance is compared with standard linear equalizer (LE) and RAKE receiver. Numerical and simulation results show that the MMSE DFE exhibits significant performance improvement over the standard linear equalizer (LE) and RAKE receiver.

Keywords

Decision Feedback Equalizer, Multiple Access Interference (MAI), RAKE Receiver, Transmit Diversity, Wideband Code-Division Multiple-Access (WCDMA), Bit Error Rate (BER)

Conflicts of Interest

The authors declare no conflicts of interest.

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