Adaptive MIMO switching of 2×2 MIMO system for WiMAX technology

Abstract

The growth in traffic volume and the increase in many new services have forced the change of wireless configuration and transmission schemes. WiMAX (Worldwide Interoperability for Microwave Access) system is considered as one technology to ground the broadband access facility by providing a variety of modulation and transmission schemes. MIMO (Multiple Input Multiple Output) technique is employed in WiMAX system to provide a higher data rate and improve a spectral efficiency. The MIMO schemes based on WiMAX standard are determined by various choices of either space-time coding or spatial multiplexing in which each choice offers a different system performance. In this paper, the adaptive MIMO switching has been proposed to maintain the best BER (Bit Error Rate) efficiency of data transmission among various choices of MIMO schemes in WiMAX system. The results reveal that the proposed system achieves a significant improvement when using adaptive MIMO switching instead of using only either spatial multiplexing or space-time coding.