Transmission channel estimating device, transmission channel estimating method and receiving apparatus

A method for estimating a transmission channel which is carried out by a transmission channel estimating device including a known-signal-sequence storage unit for storing a known signal sequence which is the same as a known signal sequence inserted in a reception signal, a transversal filter unit including a plurality of taps, and a tap-coefficient storage unit for storing tap coefficients,

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