Patent · US Active

Reduced feedback transmit beamforming

US8233556B2 · kind B2 · utility

13Cited by
3References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 11, 2007
Grant dateJul 31, 2012
Priority date
Expiry dateOct 26, 2029

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L1/06
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

A method and system for reduced feedback transmit beamforming computes a matrix of channel transfer function coefficients. The matrix of channel transfer function coefficients is compressed by applying a rotation matrix having orthogonal columns to the matrix of channel transfer function coefficients to produce a compressed transfer function matrix having a reduced number of non-zero coefficients. The compressed matrix is fed back to a transmitting unit. Decompression of the transfer function coefficient matrix is not required. This compression does not cause any performance degradation for transmit beamforming. The transmitting unit computes a set of beamsteering coefficients from the compressed matrix and applies the coefficients to signals prior to transmission. The beamformed signals are transmitted to the receiving unit and post-coded to allow the receiving unit to see an effective diagonalized channel.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.