Communication apparatus and estimation method

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.

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.