Macrodiversity packet combining for the IEEE 802.11a uplink

The paper proposes and analyzes a packet-level macrodiversity combining scheme for improving the performance of the uplink of IEEE 802.11a networks operating in infrastructure mode. By receiving the mobile station´s signal at three equidistant access points, a gain of between 6 dB and 8 dB is observed at a packet error rate of 10^-2 when the receiver is able to estimate the channel perfectly. A similar gain is found when the receiver operates without channel state information and must estimate the channel. Results are presented showing the improvement in packet error rate and throughput for several different mobile station positions. It is found that the gain due to macrodiversity combining diminishes as the mobile station moves closer to a single access point.