Patent ID: 7873112

Claim:
An Orthogonal Frequency Division Multiplexing (OFDM) receiver comprising: an antenna selecting means for sequentially selecting at least two antennas; a non-delay symbol outputting means for, when one antenna is selected by the antenna selecting means, outputting a symbol of an OFDM signal received by the one antenna as a first non-delay symbol and, when another antenna is selected by the antenna selecting means, outputting a symbol of an OFDM signal received by the other antenna as a second non-delay symbol; a delay symbol outputting means for, when one antenna is selected by the antenna selecting means, delaying a symbol of an OFDM signal received by the one antenna by a predetermined amount of time T−Tg equivalent to a difference of a symbol period T of the OFDM signal and a guard interval period Tg and outputting the delayed symbol as a first delay symbol and, when another antenna is selected by the antenna selecting means, delaying a symbol of an OFDM signal received by the other antenna by a predetermined amount of time T−Tg equivalent to a difference of a symbol period T of the OFDM signal and a guard interval period Tg and outputting the delayed symbol as a second delay symbol; a first calculating means for calculating a first moving average integration value (first moving average integration value: A I ) of the first non-delay symbol and the first delay symbol in the guard interval period Tg and calculating a second moving average integration value (second moving average integration value: B I ) of the second non-delay symbol and the second delay symbol in the guard interval period Tg; a second calculating means for calculating a third moving average integration value (third moving average integration value: A O ) of the first non-delay symbol and the first delay symbol in an effective symbol period Tu subsequent to the guard interval period Tg and calculating a fourth moving average integration value (fourth moving average integration value: B O ) of the second non-delay symbol and the second delay symbol in an effective symbol period Tu subsequent to the guard interval period Tg; and a judging means for judging which C/N ratio of the two antennas selected by the antenna selecting means is favorable based on the first and second moving average integration values (A I and B I ) and the third and fourth moving average integration values (A O and B O ).