Abstract
Minimum selection generalized selection combining (MS-GSC) scheme has been proposed as a power-saving variant of the generalized selection combining (GSC). Existing performance results of the MS-GSC scheme focus on noise-limited environment, which is an idealized scenario that may not be applicable in practice. This paper addresses the effect of co-channel interference on the performance of multiuser systems over multipath slowly varying and frequency flat fading channels when discrete-rate adaptive MS-GSC based schemes are employed. The adaptation thresholds are adjusted based on the instantaneous combined signal-to-noise ratio (SNR) to improve the desired user spectral efficiency or to reduce the processing power requirement. To clarify the effect of co-channel interference on the performance of the two adaptive schemes, analytical formulations for various performance measures are given, assuming independent and identically distributed Rayleigh fading models. These performance results are obtained using the new analytical expressions for the statistics of the combined signal-to-interference-plus-noise ratio (SINR) presented in this paper. Some numerical results, which are validated by Monte Carlo simulations, are provided to compare the performance of the two adaptive schemes for different system parameters.