Performance Evaluation of MIMO Wi MAX Network

In wireless communication system the transmitted signals from mobile station are reflected and scattered by the surrounding objects. This causes the signals to travel with multiple paths, so it arrived to the base station with different lengths and attenuations. This is known as multipath propagation. Fading problems are consequences of multipath propagation, which leads to decrease the data rate in Broadband Wireless Access (BWA) systems. The multipath fading problem can be solved using antenna diversity techniques. Multiple-Input Multiple-Output (MIMO) techniques are important to provide significant performance improvements for BWA systems such as the IEEE 802.16e, which known as mobile WiMAX systems. WiMAX systems define the physical (PHY) layer and Medium Access Control (MAC) layer for mobile and portable BWA systems. In this paper, the performances of MIMO based WiMAX system have been investigated with comparing to other two techniques, namely, Single-Input Single-Output (SISO), Multiple-Input Single-Output (MISO). The simulation results show that the system performances, in terms of Bit Error Rate (BER) of WiMAX system can be improved using MIMO technique.