A combined OFDM/SDMA approach for WLAN
New york :Ieee
Engineering sciences. Technology
VTC ... : IEEE VTS ... vehicular technology conference. - Piscataway
49th IEEE Vehicular Technology Conference (VTC 99), MAY 16-JUN 20, 1999, HOUSTON, TX
Wireless LANs (WLANs) still offer low capacity compared to wired LANs. The two major obstacles towards increasing the capacity are (a) distortion due to the indoor channel and (b) limitations on the bandwidth-power budget. In this paper we propose an OFDM/SDMA approach that combines Orthogonal Frequency Division Multiplexing (OFDM), for multipath channel distortion mitigation, with SDMA, for bandwidth efficiency. In addition, our approach concentrates ail SDMA functionality in the basestation, which reduces the overall system cost. We give algorithms for both the uplink and downlink, determine their performance and analyse their implementation complexity. It is shown that OFDM/SDMA enables high-capacity WLANs at reasonable implementation complexity.