MIMO system with multiple spatial multiplexing modes

摘要

A MIMO system supports multiple spatial multiplexing modes for improved performance and greater flexibility. These modes may include (1) a single-user steered mode that transmits multiple data streams on orthogonal spatial channels to a single receiver, (2) a single-user non-steered mode that transmits multiple data streams from multiple antennas to a single receiver without spatial processing at a transmitter, (3) a multi-user steered mode that transmits multiple data streams simultaneously to multiple receivers with spatial processing at a transmitter, and (4) a multi-user non-steered mode that transmits multiple data streams from multiple antennas (co-located or non co-located) without spatial processing at the transmitter(s) to receiver(s) having multiple antennas. For each set of user terminal(s) selected for data transmission on the downlink and/or uplink, a spatial multiplexing mode is selected for the user terminal set from among the multiple spatial multiplexing modes supported by the system.

主权项

1. A method of transmitting data in a wireless multiple-input multiple-output (MIMO) communication system, comprising:
selecting a spatial multiplexing mode to use for data transmission from among a plurality of spatial multiplexing modes supported by the system based on whether a user terminal has performed calibration so that the user terminal can estimate a channel response for a downlink based on a pilot received via an uplink, the plurality of spatial multiplexing modes comprising at least one steered spatial multiplexing mode and a non-steered spatial multiplexing mode, wherein the steered spatial multiplexing mode includes spatial processing using eigenvectors of a channel response matrix for at least one subband; coding and modulating a plurality of data streams in accordance with a plurality of rates to obtain a plurality of data symbol streams; and using the spatial multiplexing mode, processing the plurality of data symbol streams to obtain a plurality of transmit symbol streams for transmission from a plurality of antennas.