Analytical results for BER performance of Rake Receiver in Rayleigh fading channel for UMTS environment

Under the Universal Mobile Telecommunication system (UMTS) environment the third generation (3G) system is used to integrate a wide variety of communication services such as high speed data, video & multimedia traffic. But one of the biggest draw back of wireless environment is the limited bandwidth. However, the users sharing this limited bandwidth have been increased considerably by using Space Division Multiple Access (SDMA) technique that can enhance the capacity of communication system. There are some techniques that can improve the Bit Error Rate (BER) performance of communication system, these are- Spreading Technique, Error Control Coding Technique, Multipath Diversity Technique (i.e. Rake Receiver), Smart Antenna Technique. In this paper we present the analytical results for BER performance of Rake Receiver under UMTS environment with BPSK modulation. The Standard Gaussian Approximation (SGA) is used to evaluate the performance of Rake Receiver over frequency selective Rayleigh fading channel. We examined how the BER of Rake Receiver vary with varying the different parameters such as- number of users, spreading factor, Rake fingers, Interfering cells and the value of directivity of Adaptive antenna at the base station, from the results we find that the BER performance of Rake Receiver is affected by varying these parameters and gives useful results.