Sub-band beamforming for OFDM system in practical channel condition

Orthogonal frequency division multiplexing (OFDM) is a multi-carrier technique that has recently received considerable attention for high speed wireless communication and ad hoc networks. In this paper we develop a simple pilot symbol assisted frequency domain beamforming technique for the OFDM receiver. The weight vector estimated with the proposed scheme cancels strong interference and minimizes channel impairments. We investigate different aspects of the beamforming technique in a simple AWGN environment. The performance of the proposed beamforming scheme is demonstrated for a vector channel based on actual measurement data. The applicability of computationally simple least mean square (LMS) algorithm instead of the recursive least square (RLS) algorithm is also investigated in this paper.