Performance analysis of RLS and VSS-LMS channel estimation techniques for 4G MIMO OFDM systems

In this paper recursive least (RLS) square and variable step size least mean (VSS-LMS) square adaptive channel estimator are described for multiple input multiple output (MIMO) orthogonal frequency division multiplexing (OFDM) system. Both the techniques uses adaptive estimator which are capable of updating the parameters of estimator continuously and therefore knowledge of channel and noise statistics are not necessary, only knowledge of receive signal is required. From the simulation result it is observed that RLS CE method works better in terms of quick convergence rate than VSS-LMS CE for MIMO OFDM system. In addition, the utilization of more multiple antennas at the transmitter and/ or receiver provides a much higher performance compared with fewer antennas.