Patent ID: 8532233
Filing Date: 2013-09-10
Classification: H04J,H04L

Abstract:
1. A frequency offset estimation apparatus used in a wireless communication system transmitting a preamble signal generated using a sequence where a position of a side peak in an autocorrelation property of the sequence is not dependent on frequency offset and a correlation value of the side peak changes according to the frequency offset, comprising: a correlation unit configured to calculate autocorrelation of a received preamble signal; a detection unit configured to detect a position of a side peak of the autocorrelation of the preamble signal; a calculation unit configured to calculate a main correlation value representing correlation at a position of a main peak of the autocorrelation and a side correlation value representing correlation at the position of the side peak; and an estimation unit configured to estimate the frequency offset when a sum of the main correlation value and the two side correlation values is larger than a predetermined correlation threshold value, and the estimate of the frequency offset is performed by estimating the frequency offset within a range of frequency offset by comparing the main correlation value to each of the two side correlation values and, based on the comparing of the main correlation value, further comparing the two side correlation values to each other.