Patent ID: 7558223
Filing Date: 2009-07-07
Classification: H04B,H04L

Abstract:
1. An OFDM receiving method for receiving an OFDM signal via a plurality of space paths using a plurality of receiver antennas, the OFDM signal being transmitted from at least one transmitter antenna and including a plurality of subcarriers orthogonal to each other, the subcarriers including a data carrier which is assigned transmit data and a pilot carrier which is assigned a known phase and a known amplitude, the method comprising: OFDM-demodulating each of the OFDM signals received by the plurality of receiver antennas into a plurality of receive subcarriers; estimating propagation coefficients of the plurality of space paths based on the plurality of receive subcarriers; calculating an inverse matrix of a propagation matrix whose elements are the estimated propagation coefficients; performing interference cancellation for the plurality of receive subcarriers by using the inverse matrix, and estimating transmit subcarriers multiplexed in space; calculating a reliability of the inverse matrix; extracting the pilot carrier from the estimated transmit subcarriers, and weighting the extracted pilot carrier according to the reliability; and correcting an error included in the plurality of receive subcarriers based on the weighted pilot carrier, wherein the correcting step includes: a step of estimating a temporal variation of a demodulation error of a pilot carrier by using the weighted pilot carrier; a step of estimating a temporal variation of the demodulation error for each subcarrier by interpolating the estimated temporal variation in a frequency direction; and a step of correcting the estimated propagation coefficients based on the estimated temporal variation of the demodulation error for each subcarrier.