United States Patent 7,920,533
Koo , et al. April 5, 2011
Method and apparatus for calibration and channel state feedback to support transmit beamforming in a MIMO system
Abstract
A method and apparatus for calibration and channel state feedback to support transmit beamforming in a multiple-input multiple-output (MIMO) system are disclosed. For radio frequency (RF) calibration, a first station (STA) sends a calibration request to a second STA, and the second STA sends a sounding packet to the first STA. The first STA receives the sounding packet, performs at least one channel measurement and performs calibration based on the channel measurement. For channel state feedback, the first STA sends a channel state feedback request to the second STA. The second STA sends a sounding packet to the first STA. The first STA receives the sounding packet and performs at least one channel measurement with the sounding packet. The first STA then calculates a steering matrix for transmit beamforming based on the channel measurement.
--------------------------------------------------------------------------------
Inventors: Koo; Chang-Soo (Melville, NY), Wang; Jin (Central Islip, NY), Olesen; Robert Lind (Huntington, NY), Chandra; Arty (Manhasset Hills, NY), Voltz; Peter J. (Commack, NY), Yen; Chia-Pang (Regal Park, NY)
Assignee: InterDigital Technology Corporation (Wilmington, DE)
Appl. No.: 11/680,694
Filed: March 1, 2007
--------------------------------------------------------------------------------
Related U.S. Patent Documents
--------------------------------------------------------------------------------
Application Number Filing Date Patent Number Issue Date
60777835 Mar., 2006
60780623 Mar., 2006
60839846 Aug., 2006
--------------------------------------------------------------------------------
Current U.S. Class: 370/338 ; 370/310; 370/328; 370/334; 455/115.1; 455/63.1
Current International Class: H04W 4/00 (20090101); H04B 7/00 (20060101); H04B 17/00 (20060101); H04B 1/00 (20060101)
Field of Search: 370/328-350 455/69,115.1,60-63.1
PPP
"Intellectuals solve problems; geniuses prevent them." - Albert Einstein
