Combined spatial multiplexing and STBC to provide throughput enhancements to next generation WLANs

Abstract

Recently, there has been an explosion of growth in research on MIMO (Multiple Input Multiple Output) systems. Current WLAN systems such as IEEE 802.11a and 802.11g Wireless Local Area Networks (WLANs) employ Coded Orthogonal Frequency Division Multiplexing (COFDM) and provide data rates of up to 54 Mbps in a 20MHz bandwidth. In this paper, space-time block coding (STBC) and spatial multiplexing MIMO techniques are considered as a means of enhancing the performance of COFDM WLANs. A hybrid 4x4 scheme is presented that combines spatial multiplexing and STBC to provide both increased throughput and diversity. Results showed that the proposed scheme can provide good performance even under correlated channel