PROPAGATION PATH VARIATION ESTIMATING DEVICE AND PROPAGATION PATH VARIATION ESTIMATING METHOD

摘要

A propagation variation estimating device for estimating a variation of a radio propagation path characteristic due to Doppler shift fading by estimating a maximum Doppler frequency by Fourier transformation of a reference signal included in a reception signal, comprising, for example, a threshold judging section (104) for comparing the magnitude of a maximum past Doppler frequency estimate with a predetermined threshold and judging which is larger, an FFT point selection section (105) for reducing the sample frequency and the number of samples of the Fourier transform if the result of the comparison shows that the maximum Doppler frequency estimate is smaller than the threshold, and an FFT section (101).