A transmission apparatus for performing radio communication with a first type of receiving apparatus which can detect not more than N (N is an integer greater than or equal to one) 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, the transmission apparatus comprising: (N+1) or more transmission antennas (1a, 1b) 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 (1a, 1b), wherein: the control section exercises control so as to use a first radio resource for outputting known signals 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 a known signal used by the second type of receiving apparatus from at least one of the first transmission antenna and the second transmission antenna; characterized in that 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. (N+1) or more transmission antennas (1a, 1b) 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 (1a, 1b), wherein: the control section exercises control so as to use a first radio resource for outputting known signals 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 a known signal used by the second type of receiving apparatus from at least one of the first transmission antenna and the second transmission antenna; characterized in that 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. the control section exercises control so as to use a first radio resource for outputting known signals 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 a known signal used by the second type of receiving apparatus from at least one of the first transmission antenna and the second transmission antenna; characterized in that 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.