Patent ID: 8514912
Filing Date: 2013-08-20
Classification: H04B

Abstract:
1. A search frequency correction method comprising: (a) obtaining correlation values by correlating a received signal that is modulated with direct sequence spread spectrum modulation and a replica code of a spread code for each of I and Q components within a frequency search range including a search center frequency; (b) obtaining accumulated correlation values by accumulating the correlation values for each of the I component and the Q component for a time period corresponding to a polarity inversion interval; (c) obtaining long-term accumulated values for each of the I component and the Q component using the accumulated correlation values for a time period longer than the polarity inversion interval; (d) determining an error of the search center frequency based on the long-term accumulated values; and (e) correcting the search center frequency using the error, wherein the obtaining the long-term accumulated values includes calculating I addition of the accumulated correlation values for the I component, I subtraction of the accumulated correlation values for the I component, Q addition of the accumulated correlation values for the Q component and Q subtraction of the accumulated correlation values for the Q component, and the determining the error includes