Patent ID: 7961799
Filing Date: 2011-06-14
Classification: H04L

Abstract:
1. A joint channel and frequency offset estimation apparatus based on a Multi-Band-Orthogonal Frequency Division Multiplexing (MB-OFDM) system, comprising: a channel estimator for receiving a Fourier-transformed OFDM signal, and calculating results of channel estimation using a Linear Minimum Mean Square Error (LMMSE) channel estimation, which minimizes a Mean Square Error (MSE) between an actual channel value and an estimated channel value; an autocorrelation unit for calculating an autocorrelation value using the results, which are calculated through the channel estimator, in which a frequency offset is considered; and a frequency offset estimator for calculating a frequency offset, having a maximum value calculated by the autocorrelation unit, and estimating an actual frequency offset, wherein the frequency offset estimator uses a resulting value of the autocorrelation unit, but maximum and minimum ranges of a hypothetical frequency offset are preset according to the MB-OFDM system, and thus the frequency offset is estimated through a binary search, wherein the hypothetical frequency offset has the same value as the actual frequency offset, and the resulting value of autocorrelation of the estimated channel have a maximum value, and wherein as a difference between the hypothetical frequency offset and the actual frequency offset increases, the resulting autocorrelation value decreases.