An OFDM transmission apparatus configured to communicate with a reception apparatus, the OFDM transmission apparatus comprising: a serial/parallel conversion section (31, 32, 33) configured to convert a data from serial to parallel; (i) a variable-spreading-factor spreading section configured to perform spreading the data with rotation orthogonal codes and with a variable spreading factor based on a control information A for determining the variable spreading factor, wherein the spreading factor indicates how many sub-carriers are used for sending one piece of data, wherein according to the control information A the variable spreading factor is changed depending on transmission power required, and wherein the control information A is changed in accordance with the number of sub-carriers used; (ii) a sub-carrier allocation section configured to allocate at least one spread signals to a plurality of sub-carriers in accordance with a control information D for allocating the plurality of sub-carriers; (iii) an inverse discrete Fourier transform section configured to perform inverse discrete Fourier transform on the allocated at least one spread signals; (iv) a control section configured to control a limit of average input power for transmitting the data signals, according to the number of the at least one spread signals, wherein the more the number of the at least one spread signals is larger, the more the amount of the limit of average input power is larger; and (v) a RF section configured to transmit the at least one spread signals performed inverse discrete Fourier transform, wherein the RF section includes a variable-gain amplifier and a high-output amplifier, wherein the control information A originates from the control section, and the control information D originates from the control section. a serial/parallel conversion section (31, 32, 33) configured to convert a data from serial to parallel; (i) a variable-spreading-factor spreading section configured to perform spreading the data with rotation orthogonal codes and with a variable spreading factor based on a control information A for determining the variable spreading factor, wherein the spreading factor indicates how many sub-carriers are used for sending one piece of data, wherein according to the control information A the variable spreading factor is changed depending on transmission power required, and wherein the control information A is changed in accordance with the number of sub-carriers used; (ii) a sub-carrier allocation section configured to allocate at least one spread signals to a plurality of sub-carriers in accordance with a control information D for allocating the plurality of sub-carriers; (iii) an inverse discrete Fourier transform section configured to perform inverse discrete Fourier transform on the allocated at least one spread signals; (iv) a control section configured to control a limit of average input power for transmitting the data signals, according to the number of the at least one spread signals, wherein the more the number of the at least one spread signals is larger, the more the amount of the limit of average input power is larger; and (v) a RF section configured to transmit the at least one spread signals performed inverse discrete Fourier transform, wherein the RF section includes a variable-gain amplifier and a high-output amplifier, wherein (i) a variable-spreading-factor spreading section configured to perform spreading the data with rotation orthogonal codes and with a variable spreading factor based on a control information A for determining the variable spreading factor, wherein the spreading factor indicates how many sub-carriers are used for sending one piece of data, wherein according to the control information A the variable spreading factor is changed depending on transmission power required, and wherein the control information A is changed in accordance with the number of sub-carriers used; (ii) a sub-carrier allocation section configured to allocate at least one spread signals to a plurality of sub-carriers in accordance with a control information D for allocating the plurality of sub-carriers; (iii) an inverse discrete Fourier transform section configured to perform inverse discrete Fourier transform on the allocated at least one spread signals; (iv) a control section configured to control a limit of average input power for transmitting the data signals, according to the number of the at least one spread signals, wherein the more the number of the at least one spread signals is larger, the more the amount of the limit of average input power is larger; and (v) a RF section configured to transmit the at least one spread signals performed inverse discrete Fourier transform, wherein the RF section includes a variable-gain amplifier and a high-output amplifier, wherein the control information A originates from the control section, and the control information D originates from the control section.