Composite Channel Estimation in MIMO-OFDM system with enhanced spectral efficiency

Pilot Added Channel Estimation (PACE) for Orthogonal Frequency Division Multiplexing (OFDM) in multiple transmitting antennas causes inter-antenna interference. This can be mitigated by the use of null sub-carriers. However the presence of null sub-carriers degrades the spectral efficiency of OFDM system This paper proposes an efficiency enhancing channel estimation method by estimating composite Channel State Information (CSI) for the given receiving antenna.