Wireless communication method, wireless communication system, and transmitter

A wireless communication system that transmits a signal from a transmission device to a reception device, the wireless communication system comprising:

• a precoding circuitry configured to precode a stream of a transmission signal in a time domain by using an FIR filter;
• a transmission power control circuitry configured to control a transmission power of the stream precoded by the precoding circuitry;
• an amplifier that amplifies the stream precoded by the precoding circuitry under control of the transmission power control circuitry;
• and
• a tap length control circuitry configured to perform control for changing a tap length in the precoding circuitry such that the tap length is decreased in a case where a magnitude of a last tap coefficient in the precoding circuitry is small and the tap length is increased in a case where the magnitude is large, with respect to a threshold value calculated on the basis of quality information of a received signal fed back from the reception device that has received the stream amplified by the amplifier or quality information of a received signal calculated by using at least characteristics of the amplifier.

A transmission device comprising:

• a precoding circuitry configured to precode a stream of a transmission signal in a time domain by using an FIR filter;
• a transmission power control circuitry configured to control a transmission power of the stream precoded by the precoding circuitry;
• an amplifier that amplifies the stream precoded by the precoding circuitry under control of the transmission power control circuitry;
• and
• a tap length control circuitry configured to perform control for changing a tap length in the precoding circuitry such that the tap length is decreased in a case where a magnitude of a last tap coefficient in the precoding circuitry is small and the tap length is increased in a case where the magnitude is large, with respect to a threshold value calculated on the basis of quality information of a received signal fed back from the reception device that has received the stream amplified by the amplifier or quality information of a received signal calculated by using at least characteristics of the amplifier.