MULTI-ANTENNA SYSTEM USING ADAPTIVE BEAMFORMING

• US 20110033015A1
• Filed: 12/17/2009
• Published: 02/10/2011
• Est. Priority Date: 08/06/2009
• Status: Active Grant

• Current Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Original Assignee: Samsung Electro-Mechanics Co., Ltd. (Samsung Group)
• Inventors: PARK, Chul Gyun, JO, Kyung Tae, PARK, Joun Sup, KO, Young Chai
• Granted Patent: US 8,401,133 B2
• Time in Patent Office: Days
• US Class Current: 375/347
• CPC Class Codes: H04B 17/336 Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• CPC Class Codes: H04B 7/084 Equal gain combining, only phase adjustments antenna beam scanning or forming by phase or amplitude control H01Q3/26, e.g. phased arrays

Abstract

A multi-antenna system using adaptive beamforming includes a phase shift unit, a signal combination unit, a frequency down-converter, and an analog-to-digital (A/D) converter, and a beamforming control unit. The phase shift unit includes a plurality of phase shifters which shift the phases of signals received from a plurality of antennas. The signal combination unit combines phase-shifted signals output from the plurality of phase shifters. The frequency down-converter down-converts a signal output from the signal combination unit into a baseband signal. The A/D converter converts the baseband signal into a digital signal. The beamforming control unit searches for a weight vector higher than a preset threshold signal-to-noise ratio (SNR) when a reception SNR of the digital signal output from the A/D converter is lower than the threshold SNR, and changes a currently set weight vector into the searched weight vector to provide to the phase shift unit.

Claims

1. A multi-antenna system using adaptive beamforming, comprising:

a phase shift unit comprising a plurality of phase shifters which shift the phases of signals received from a plurality of antennas, each of the phase shifters shifting the phase of the corresponding received signal, depending on a preset weight vector;

a signal combination unit combining phase-shifted signals output from the plurality of phase shifters;

a frequency down-converter down-converting a signal output from the signal combination unit into a baseband signal;

an analog-to-digital (A/D) converter converting the baseband signal output from the frequency down-converter into a digital signal; and

a beamforming control unit searching for a weight vector higher than a preset threshold signal-to-noise ratio (SNR) among a plurality of prepared weight vectors when a reception SNR of the digital signal output from the A/D converter is lower than the threshold SNR, and changing a currently set weight vector into the searched weight vector to provide to the phase shift unit.

2. The multi-antenna system of claim 1, wherein the beamforming control unit comprises:

a codebook comprising a plurality of weight vectors which are preset for the beamforming of the plurality of antennas;

an SNR measurement unit measuring the reception SNR of the digital signal output from the A/D converter;

an SNR comparison unit comparing the reception SNR from the SNR measurement unit with the preset threshold SNR; and

a weight vector control unit initially setting the preset weight vector and maintaining the currently set weight vector when the reception SNR is higher than the threshold SNR, or sequentially searching for a weight vector higher than the threshold SNR among the plurality of weight vectors prepared in the weight vector codebook and changing the currently set weight vector into the searched weight vector when the reception SNR is not higher than the threshold SNR.

3. The multi-antenna system of claim 2, wherein the weight vector codebook comprises a plurality of weight vectors corresponding to combinations of the plurality of antennas in a spaced direction, and each of the weight vectors comprises phase shift values for the signals received from the plurality of antennas.