In this paper, a comparative investigation on various channel estimation and equalization algorithms for OFDM based high rate wireless MAN networks is presented and analyzed in terms of mean-square error (MSE), bit-error rate (BER) and computational complexity. We consider some of the proposed algorithms regarding channel estimation and equalization for typical OFDM systems in the literature, and then conclude an efficient and suitable scheme with some complexity reduction suggestions, in implementing a practical MMDS application of the IEEE 802.16a standard WMAN networks based on the OFDM technique. The system performance under various configurations of the proposed physical layer based on the standard specifications especially for different coding & modulation combinations (PHY modes) as well as uncoded case, be evaluated