Variable Forgetting Factor RLS Algorithm-Based Channel Estimator for MC-IDMA Communication Systems

There are different types of technologies that are in use for multi-user wireless communication systems. In this article, a relatively new multi-user scheme, Multi-Carrier Interleave Division Multiple Access (MC-IDMA) is considered. The scheme is an attractive multiuser technique that has generated a large interest in the research community. In this article the channel estimation area of the wireless communication system is investigated. A variable forgetting factor-recursive least mean square (VFF-RLS) algorithm is proposed for channel impulse response (CIR) estimation in the MC-IDMA systems. The performance of the proposed adaptive VFF-RLS based-time domain iterative channel estimator is validated in comparison with the LMS-based channel estimator and another channel estimation scheme employing both channel transfer function based on sequential linear minimum mean square error estimator and the adaptive prediction of the time domain CIR earlier proposed in literature. The simulation results indicate that the proposed VFF-RLS based-time domain iterative channel estimator outperforms its counterparts and it is a good compromise in terms of performance and computational complexity.