| 摘要 |
<P>PROBLEM TO BE SOLVED: To enhance estimation accuracy of the maximum doppler frequency even when affected by factors except for fading fluctuation by setting an optimum averaging section length for averaging an amplitude. <P>SOLUTION: Channel estimation parts 103-1 to 103-n calculate amplitudes and phase differences of respective paths for each predetermined time period from a reception signal. A phase difference calculation part 109 averages the amplitudes of the respective paths to calculate an amplitude average value respectively and averages the phase differences of the respective paths to calculate a phase difference average value respectively in a first averaging section length calculated from a previously estimated maximum doppler frequency, and weights and combines the phase difference average value between the respective paths depending on the amplitude average value. A doppler frequency calculation part 112 estimates the maximum doppler frequency based on the phase difference average value weighted and combined by the phase difference calculation part 109. <P>COPYRIGHT: (C)2013,JPO&INPIT |
