Patent ID: 7158793
Filing Date: 2007-01-02
Classification: H04B

Abstract:
1. A method for beam shaping in a radio communication system having a plurality of subscriber stations and a base station which has an antenna apparatus with a plurality of antenna elements, comprising: transmitting a downlink signal to a subscriber station from each antenna element; for each of the antenna elements, weighting the downlink signal transmitted thereby with a weighting coefficient w forming a plurality of first weighting vectors in an initialization phase, the first weighting vectors being formed so as to be orthogonal to one another: cyclically redefining the current weighting vector for each time slot of the downlink signal, the current weighting vector being cyclically redefined based on the first weighting vectors; producing a first spatial covariance matrix of the downlink signal; determining eigenvectors of the first spatial covariance matrix; and selecting the first weighting vectors from among the eigenvectors of the first spatial covariance matrix, wherein short-term covariance matrices are formed for each tap of the downlink signal; and the first spatial covariance matrix is obtained by averaging the short-term covariance matrices over all taps.