Patent ID: 8750276

Claim:
A transmission apparatus for performing radio communication with a first type of receiving apparatus which can detect not more than N transmission antennas from a received signal and a second type of receiving apparatus which can detect more than N transmission antennas from a received signal, where N is an integer greater than or equal to one, the transmission apparatus comprising: (N+1) or more transmission antennas including a first transmission antenna and a second transmission antenna; and a control section which assigns a radio resource to a signal outputted from each of the (N+1) or more transmission antennas, wherein: the control section exercises control so as to use a first radio resource for outputting known signals α 0 and α 1 used by the first type of receiving apparatus and the second type of receiving apparatus from the first transmission antenna and the second transmission antenna and to use a second radio resource for outputting known signals β 0 and β 1 used by the second type of receiving apparatus from the first transmission antenna and the second transmission antenna, respectively; and a timing difference between the first radio resource and the second radio resource is smaller than or equal to a first determined difference and a frequency difference between the first radio resource and the second radio resource is smaller than or equal to a second determined difference, wherein the known signal α 0 outputted from the first transmission antenna, the known signal α 1 outputted from the second transmission antenna, the known signal β 0 outputted from the first transmission antenna, and the known signal β 1 outputted from the second transmission antenna satisfy β 0 =α 1 * and β 1 =−α 0 *, where * indicates a complex conjugate operation.