Patent ID: 7522939

Claim:
A radio communication apparatus that has first, second, third and fourth receiving antennas for receiving incoming radio waves, and carries out communication with mobile communication terminals, said radio communication apparatus comprising: a received beam generating section for generating first and second received beams which are perpendicular to each other and spatially separated by assigning weights to received signals fed from the first, second, third and fourth receiving antennas by using first and second received beam weights utilizing Fourier transform, said receiving beam generating section assigning weights to the received signals fed from the first, second, third and fourth receiving antennas using the first received beam weight of a fixed weight to generate a first received beam having a major lobe in a certain direction and a grating lobe in a direction 180 degrees opposite to the certain direction; and assigning weights to the received signals using the second received beam weight of a fixed weight to generate a second received beam which is orthogonal to the first received beam, and including a major lobe in a certain direction and a grating lobe in a direction 180 degrees opposite to the certain direction; a first signal arriving timing detecting section for measuring a received signal level using the first received beam fed from said received beam generating section and a known reference signal set for each of the individual mobile communication terminals, and for outputting signal arriving timing information when the first received beam includes the reference signal; a second signal arriving timing detecting section for measuring a received signal level using the second received beam fed from said received beam generating section and a known reference signal set for each of the individual mobile communication terminals, and for outputting signal arriving timing information when the second received beam includes the reference signal; and a demodulating section for receiving the first and second received beams from said received beam generating section, and for outputting demodulation data by performing maximal-ratio combining in response to the signal arriving timing information fed from said first and second signal arriving timing detecting sections.