MIMO beamforming method and method of constructing a differential codebook for a wireless network

摘要

A MIMO beamforming method comprises receiving at a base station information regarding a difference between an ideal beamforming matrix and an averaged beamforming direction, using the information to construct a beamforming matrix at the base station, and performing a beamforming operation using the reconstructed beamforming matrix. Alternatively, the method comprises computing at a subscriber station an averaged beamforming direction, computing at the subscriber station a quantization index corresponding to a differential matrix in a differential codebook, and transmitting the quantization index across a wireless channel of the wireless network. The differential codebook may be constructed by identifying a codebook center and transforming a predefined codebook that is stored in a memory of a component of the wireless network.

主权项

1. A base station for a wireless network, comprising:
a receiver to receive a pair of indices from a mobile device over a communication channel of a closed-loop multiple-input and multiple-output (MIMO) system, the pair of indices to comprise a first index to represent a first direction for a set of transmitter antennae computed from wideband information for the communication channel, and a second index to represent a second direction for the transmitter antennae relative to the first direction, the second index to comprise a differential value representing a difference in beamforming direction between the first and second directions, and the first direction to comprise an averaged beamforming direction.