SCHEDULING ALGORITHMS FOR IEEE 802.11 MULTI-USER (MU) MULTIPLE-INPUT MULTIPLE-OUTPUT (MIMO) COMMUNICATION SYSTEMS

摘要

A method is provided for wirelessly transmitting from a transmitter to one or more receivers within a multi-user (MU) multiple-input and multiple-output (MIMO) communication system. A number of concurrent (spatial) streams are dynamically allocated in a MU-MIMO transmission to each of a plurality of served receivers to maximize total data transmitted on each transmission. Streams are allocated according to a corresponding transmission queue length for each receiver and the number of receive antennas used by each of the served receivers. A transmission timer is started upon sending the transmission. A random backoff counter is also started upon one of either: (a) expiration of the transmission timer or (b) receipt of data at a transmission queue. A new transmission is sent upon expiration of the random backoff counter if the transmission timer has expired. Otherwise, the random backoff counter is restarted one or more times until the transmission timer has expired.