Abstract: The most widely used modulation technique for wireless communications is Orthogonal Frequency Division Multiplexing (OFDM).The demand of high bit rate has increased in recent wireless communication networks. Multiple Input Multiple Output (MIMO) technology has the ability to improve the problem of traffic capacity in the wireless networks. MIMO systems can be defined as the use of multiple antennas at both the transmitting and receiving ends of a wireless communication network. The systems MIMO-OFDM (multiple input and multiple output orthogonal frequency division multiplexing) system is a new wireless broadband technology which has gained great popularity for its capability of high rate transmission and its robustness against multipath fading. Fading effects are the effects to be considered at the receiver. Fading effects must be mitigated at the receiver before demodulation by using equalization techniques. In this paper Zero Forcing equalization and Minimum Mean Square Error equalization techniques are presented for reduction in bit error rate for the BPSK modulation technique. The performance is evaluated in terms of BER versus SNR. The performance of MIMO-OFDM system is evaluated by using different equalizers.
Keywords: MIMO, OFDM, BER, ZF and MMSE EQUALIZERS.