| 摘要 |
PROBLEM TO BE SOLVED: To realize precise correction even when large frequency deviation occurs by roughly correcting a frequency with the detection of frequency deviation in a pilot block and finely correcting the frequency with the detection of frequency deviation between the pilot blocks. SOLUTION: A frequency correction circuit is constituted of a pilot symbol detection part 1, an inter-symbol phase difference detection processing part 2, an inter-pilot block phase difference detection processing part 3, an inter- symbol phase difference averaging processing part 4, an inter-pilot block phase difference averaging processing part 5, a frequency correction quantity calculation processing part 6 and a digital-analog converter 7. A signal after inverse spread is inputted to the detection part with communication where a known symbol pilot block is periodically inserted into a pilot synchronism detection signal. A pilot symbol is extracted. In the processing parts 2 and 3, inter-pilot block frequency deviation and inter-pilot block frequency deviation are corrected, the frequency is roughly corrected in the former and the frequency is finely corrected in the latter. |
