Exploitation of multiuser diversity in spatial and time domain by opportunistic communication system using an Omni-directional antenna at BS

This paper exploits the concept of diversity using omni-directional antenna at BS, where different users are communicating with BS from different locations but at same frequency in flat fading and frequency selective environments. The opportunistic communication method has been implemented using Matlab Rayleigh and Spatial channel model (SCM) developed by 3rd generation partnership project (3GPP). The main focus is on comparison of results using SCM and Matlab Rayleigh channel and is shown with the help of simulations that SCM provides an improvement in terms of bit error rate (BER) as compared to Matlab Rayleigh Channel. The BER performance of SCM systems is much better thereby showing an improvement of about 5 dB in flat fading environment that happens because of exploitation of spatial diversity offered by SCM. In case of frequency selective fading environment there is an improvement of 2-3 dB for two users while using SCM as compared to Matlab Rayleigh channel by exploitation of diversity in spatial and time domain.