Patent ID: 7394859

Claim:
An apparatus for receiving an OFDM (Orthogonal Frequency Division Multiplexing) signal multiplexing a reference symbol having known amplitude and phase characteristic to at least one of a plurality of sub-carriers orthogonal to each other, comprising: a converter which converts the OFDM signal into a plurality of sub-carriers; an extraction circuit to extract the reference symbol from at least one of a plurality of sub-carriers; an estimation circuit to estimate a transmission channel distortion for each of the sub-carriers based on the known amplitude and phase characteristic of the reference symbol to obtain a plurality of channel estimation results; an estimation processing circuit which adds the channel estimation results every several sub-carriers of the sub-carriers to obtain a plurality of added values, the several sub-carriers including a first sub-carrier corresponding to the at least one of the several sub-carriers, a second sub-carrier adjacent to a high-band side of the first sub-carrier and a third sub-carrier adjacent to a low-band side of the first sub-carrier; a calculating unit configured to obtain amplitude and phase correction values on the first sub-carrier by averaging the added results, while the first sub-carrier is shifted sequentially; a correction circuit to correct amplitude and phase of each of the plurality of sub-carriers based on the amplitude and phase correction values; and wherein the estimation processing circuit multiplies the result of the first sub-carrier, the result of the second sub-carrier, and the result of the third sub-carrier by respective weight coefficients, and adds the multiplied values.