Patent ID: 7817967
Filing Date: 2010-10-19
Classification: H01Q,H04B

Abstract:
1. A method of forming a downlink beam in an adaptive antenna system of a communications system, comprising: receiving vectors of signals including signals transmitted by user terminals of the communications system and signals transmitted by transceivers of an independent communications system; obtaining spatial information for the user terminals of the communications system and the transceivers of the independent communications system; generating complex transmitting weights that form spatial nulls directed at the transceivers of the independent communications system; and transmitting a downlink communications signal using the complex transmitting weights, wherein obtaining spatial information for the user terminals of the communications system and the transceivers of the independent communications system comprises obtaining the spatial information using the received vectors of signals, wherein obtaining spatial information comprises generating estimates of an array covariance matrix using the signals transmitted by the user terminals of the communications system and the signals transmitted by the transceivers of an independent communications system, and wherein generating estimates of the array covariance matrix comprises: estimating a covariance matrix for the transceivers of the independent communications system; estimating a covariance matrix for the user terminals of the communications system; and deriving a composite covariance matrix by combining the covariance matrix for the transceivers of the independent communications system with the covariance matrix for the user terminals of the communications system.