Patent ID: 8422602
Filing Date: 2013-04-16
Classification: H04L

Abstract:
1. A pattern detection circuit for performing pattern detection on first input signals from a communication terminal, comprising: a first frequency domain transformer for transforming the first input signals into frequency domain signals; a frequency extractor for extracting frequency components of the frequency domain signals; and a pattern detector for performing the pattern detection based on cross-correlation values in frequency domain between the extracted frequency components and predetermined patterns, wherein between the frequency extractor and the pattern detector, further comprising: a first time domain transformer for transforming the extracted frequency components into time domain signals by a number of points that is 1/M (M is an integer equal to two or more) of the number of points to be processed in the first frequency domain transformer; and a second frequency domain transformer for transforming the time domain signals into the frequency domain signals; wherein the pattern detector performs the pattern detection on the first input signals based on cross-correlation values in frequency domain between output from the second frequency domain transformer and the predetermined patterns, the number of points to be processed in the first frequency domain transformer is set to 1/m (m is an integer equal to two or more) of the number of samples in the first input signals, and m times of the transforming processing by the first frequency domain transformer are performed repeatedly.