Patent ID: 7486720
Filing Date: 2009-02-03
Classification: H04B

Abstract:
1. A method for transmitting training frames in a multiple-input multiple-output (MIMO) system from a station B to a station A via a channel of the MIMO system, in which the station A includes N A antennas and N A SS RF modulator chains and the station B includes N B antennas and N B SS RF modulator chains, comprising: determining a first lower bound transmitting, from a station B to a station A, a long sequence of training frames for antenna selection, in which a number of frames in the long sequence of training frames is at least equal to the first lower bound; determining a second lower bound transmitting, in response to receiving the long sequence of training frames, from the station A to the station B, a short sequence of training frames for antenna selection, in which a number of frames in the short training sequence is at least equal to the second lower bound; estimating, for antenna selection in the station A, complete characteristics of the channel from the long sequence of training frames; and estimating, for antenna selection in the station B, partial characteristics of the channel from the short sequence of training frames; and selecting, in the station A, a subset of the N selecting, in the station B, a subset of the N