Patent ID: 7369511
Filing Date: 2008-05-06
Classification: H04B,H04L

Abstract:
1. A communication method for exchanging channel information between a transmitter and a receiver each including a plurality of antennas, the method comprising: constructing, at the transmitter, a request frame including a first preamble, a second preamble, and a channel information feedback request; transmitting the request frame to the receiver, wherein the first preamble is transmitted from one of the plurality of antennas of the transmitter, the second preamble is transmitted from each of the plurality of antennas of the transmitter, and the channel information feedback request is transmitted from the one of the plurality of antennas of the transmitter; receiving the request frame at the receiver, wherein the first preamble is received from one of the plurality of antennas of the receiver, the second preamble is received from each of the plurality of antennas of the receiver, and the channel information feedback request is received from the one of the plurality of antennas of the receiver; detecting, at the receiver, the channel information feedback request by a decoding based on the first preamble; estimating channel information, using the second preamble at the receiver; constructing, at the receiver, a notification frame including the estimated channel information; transmitting the notification frame to the transmitter; and receiving the notification frame at the transmitter, the notification frame responding to the request frame.