Path selection in an OFDM apparatus

摘要

An orthogonal frequency division multiplexing (OFDM) demodulating apparatus includes a delay profile creating section, a Fourier converting section (42), a pilot signal extracting section (31), a transmission path characteristic estimating section (19), an inverse Fourier converting section (20), and a window control section (21). The delay profile creating section estimates a first delay profile estimate. The inverse Fourier converting section generates a second delay profile estimate. The window control section analyses the first delay profile and the second delay profile and determines a composite delay profile for use in defining a calculation range time within which data can be recovered from the OFDM signal. The window control section selects paths to appear in the composite delay profile, which exist at a same position in both of the first and the second delay profiles, and if these paths exist a number of times greater than or equal to a threshold value. The threshold value is defined such that the threshold is set to a higher value for paths within a predetermined position from the position of the main path within the delay profile created by the inverse Fourier converting section than those for the paths at other positions.