QUALCOMM Incorporated
Correlation-based channel feedback

Abstract:

This disclosure provides methods, devices and systems for providing channel feedback for multiple spatial streams. In some implementations, the techniques involve generating distinct channel estimates for different respective sets of orthogonal spatial streams. In some implementations, the orthogonality of the different sets of orthogonal spatial streams enables the beamformee to distinguish the spatial streams to provide the separate channel estimates. The beamformee may then determine separate correlations for the different respective sets of spatial streams. In some implementations, the beamformee combines the correlations to determine an average correlation for each of a number of sets of frequency tones. The beamformee may then perform an eigenvalue decomposition on a tone-by-tone basis based on the respective average correlation and the channel estimate obtained for the tone. Because the eigenvalue decomposition may be performed on each of the two sets of spatial streams separately, the complexity involved with performing each eigenvalue decomposition is greatly reduced.