COMMUNICATION APPARATUS AND ESTIMATION METHOD
According to an aspect of the present invention, there is provided a communication apparatus including: a synchronizer configured to perform synchronization processing according to a Doppler shift on a reception signal; and an equalizer configured to perform equalization processing on a reception signal on which the synchronization processing has been performed, in which the synchronizer includes a correlator configured to output a correlation between a reception signal and a known preamble sequence and a correlation between the reception signal and a known postamble sequence, a slide correlator configured to output a sliding correlation based on an output of the correlator, and a Doppler estimator configured to estimate a Doppler shift based on the sliding correlation of the slide correlator
1 . A communication apparatus comprising:
a synchronizer configured to perform synchronization processing according to a Doppler shift on a reception signal; and
an equalizer configured to perform equalization processing on a reception signal on which the synchronization processing has been performed, wherein
the synchronizer includes
a correlator configured to output a correlation between a reception signal and a known preamble sequence and a correlation between the reception signal and a known postamble sequence,
a slide correlator configured to output a sliding correlation based on an output of the correlator, and
a Doppler estimator configured to estimate a Doppler shift based on the sliding correlation of the slide correlator.
2 . The communication apparatus according to claim 1 , wherein
the slide correlator outputs a sliding correlation based on only amplitude information of an output of the correlator.
3 . The communication apparatus according to claim 1 , wherein the correlator and the slide correlator use a fast Fourier transform (FFT) for calculation of cross-correlation.
4 . A communication apparatus comprising:
a synchronizer configured to perform synchronization processing according to a Doppler shift on a reception signal; and
an equalizer configured to perform equalization processing on a reception signal on which the synchronization processing has been performed, wherein
the synchronizer includes
a synthetic correlator configured to calculate a first cross-correlation between the reception signal and a known preamble sequence and a second cross-correlation between the reception signal and a known postamble sequence, and outputs a sliding correlation between the first cross-correlation and the second cross-correlation, and
a Doppler estimator configured to estimate a Doppler shift based on the sliding correlation of the synthetic correlator.
5 . The communication apparatus according to claim 4 , wherein
the synthetic correlator estimates the sliding correlation based on an amplitude value of a correlation between the preamble sequence and the reception signal and an amplitude value of a correlation between the postamble sequence and the reception signal.
6 . The communication apparatus according to claim 4 , wherein the synthetic correlator uses an FFT for calculation of cross-correlation.
7 . An estimation method performed by a communication apparatus including a synchronizer configured to perform synchronization processing according to a Doppler shift on a reception signal, and an equalizer configured to perform equalization processing on a reception signal on which the synchronization processing has been performed, the method comprising:
outputting a first correlation between a reception signal and a known preamble sequence and a second correlation between the reception signal and a known postamble sequence;
outputting a sliding correlation based on the first correlation and second correlation; and
estimating a Doppler shift based on the sliding correlation.
8 . An estimation method performed by a communication apparatus including a synchronizer configured to perform synchronization processing according to a Doppler shift on a reception signal, and an equalizer configured to perform equalization processing on a reception signal on which the synchronization processing has been performed, the method comprising:
calculating a first cross-correlation between the reception signal and a known preamble sequence and a second cross-correlation between the reception signal and a known postamble sequence, and outputting a sliding correlation between the first cross-correlation and the second cross-correlation, and
estimating a Doppler shift based on the sliding correlation.