Systems and methods for interference alignment in Wi-Fi

摘要

System and method embodiments are provided for interference alignment in a wireless local area network (LAN) with an overlapping basic service set (OBSS). In an embodiment, a method includes instructing a first access point (AP) in the wireless LAN to broadcast a null data packet (NDP) sounding packet to a plurality of stations when no other AP is broadcasting, wherein the NDP sounding packet comprises a plurality of long training field (LTFs), and wherein a total number of LTFs is equal to a total number of transmission streams, receiving channel beamforming (BF) information and a signal plus interference to noise ratio (SINR) from each of the stations, wherein each of the stations computes the channel BF information and the SINR from sounding packets received from each of the APs in the wireless LAN, and determining a transmission schedule according to the SINRs and the channel BF information.

主权项

1. A method in a network component for interference alignment in a wireless local area network (LAN) with an overlapping basic service set (OBSS), the method comprising:
instructing with the network component a first one of a plurality of access points (APs) in the wireless LAN to broadcast a null data packet (NDP) sounding packet to a plurality of stations when no other AP in the plurality of APs is broadcasting, wherein the NDP sounding packet comprises a plurality of long training field (LTFs), and wherein a total number of LTFs is equal to a total number of transmission streams per each AP; receiving channel beamforming (BF) information and a signal plus interference to noise ratio (SINR) from each of the plurality of stations, wherein each of the plurality of stations computes the channel BF information and the SINR from sounding packets received from each of the plurality of APs in the wireless LAN; determining a transmission schedule according to the SINRs and the channel BF information; grouping the stations according to a preferred pre-coder index, wherein each station provides a corresponding preferred pre-coder index in response to the sounding packet; comparing the SINRs per stream in a group and selecting a station from the group that provides a best SINR; recomputing a sum-rate in each group based on a selected station in each group and the selected station's corresponding SINR; selecting a group that provides a best sum-rate; selecting a pre-coder corresponding to the selected group; and scheduling the stations in the selected group from two APs.