Patent ID: 8831083

Claim:
A transmission channel estimating device for estimating a transmission channel from a reception signal in which a known signal sequence is inserted and transmission data is digitally modulated, the transmission channel estimating device comprising: a reception-signal storage unit for storing the reception signal; a known-signal-sequence storage unit for storing a known signal sequence which is the same as the known signal sequence inserted in the reception signal; a tap-coefficient storage unit for storing tap coefficients; a transversal filter unit including a plurality of taps, the transversal filter unit generating an estimated reception signal on the basis of the known signal sequence stored in the known-signal-sequence storage unit and the tap coefficients; a subtracting unit for generating an error signal on the basis of a difference between the reception signal and the estimated reception signal; a tap-coefficient updating unit for generating updated tap coefficients on the basis of the known signal sequence, the tap coefficients and the error signal to replace the tap coefficients stored in the tap-coefficient storage unit with the updated tap coefficients; and a tap-section setting unit for designating effective sections formed by a predetermined number of taps out of the plurality of taps in the transversal filter unit, wherein: the tap-section setting unit designates a first section which is set so as to include a center tap and a second section which is set so as to include the center tap, as the effective sections in the plurality of taps in the transversal filter unit, and the generation of the estimated reception signal by the transversal filter unit, the generation of the updated tap coefficients and the replacement in the tap-coefficient storage unit by the tap-coefficient updating unit are performed by generating an estimated reception signal and generating and rewriting updated tap coefficients in the tap-coefficient storage unit for the first section, and generating an estimated reception signal and generating and rewriting updated tap coefficients in the tap-coefficient storage unit for the second section.