Orthogonal frequency division multiplexing (OFDM) technique has its advantages such as high bandwidth efficiency, high bit rates and robustness with respect to multi path fading. In order to recover the transmitted signal channel estimation becomes the integral part of the system. Least square(LS), minimum mean square error(MMSE), modified least square and modified minimum mean squared error are some of the channel estimation techniques used. The performance of the various estimators for AWGN channel and Rayleigh channel for various modulation techniques like QPSK, 16 QAM and 64 QAM is discussed and analysed. In pilot arrangement, different patterns are proposed and results obtained are presented. © Research India Publications.