Patent ID: 8581570
Filing Date: 2013-11-12
Classification: H04L

Abstract:
1. A frequency error detection apparatus comprising: a known signal extraction circuit configured to extract, from a received signal in which a known signal changing periodically is inserted, the known signal; a first distributing arrangement circuit configured to distributingly arrange the known signal extracted by the known signal extraction circuit, in a fixed section; a first frequency conversion circuit configured to frequency-convert an output of the first distributing arrangement circuit to a frequency-domain signal; a first delay detection circuit configured to calculate an amount of phase variation between adjacent frequency components by delay-detecting the frequency-domain signal which is the output of the first frequency conversion circuit; a sequence generation circuit configured to generate the same sequence as the known signal changing periodically; a second distributing arrangement circuit configured to distributingly arrange the sequence generated by the sequence generation circuit, in a fixed section; a second frequency conversion circuit configured to frequency-convert an output of the second distributing arrangement circuit to a frequency-domain signal; a second delay detection circuit configured to calculate an amount of phase variation between adjacent frequency components by delay-detecting the frequency-domain signal which is the output of the second frequency conversion circuit; a correlation operation circuit configured to output a correlation value between an output of the first delay detection circuit and an output of the second delay detection circuit; and a peak detection circuit configured to detect one or more high power peaks among the correlation values, calculate a difference from a reference value and output the difference as a frequency error.