Wireless communication apparatus and wireless communication method

A wireless communication apparatus comprising:

• a plurality of antenna elements;
• a plurality of quadrature demodulators that are provided to the respective antenna elements, and that generate in-phase signals and quadrature signals of an intermediate frequency by performing quadrature demodulation on reception signals;
• a combiner that combines the in-phase signals generated by the quadrature demodulators and combines the quadrature signals generated by the quadrature demodulators;
• and
• a processor to which an in-phase signal and a quadrature signal acquired by the combiner are input, wherein
• the processor is configured to execute a process including
• applying a first frequency shift according to a reception beam direction to a first oscillation signal that is supplied to the quadrature demodulators and used for frequency conversion into the intermediate frequency,
• performing complex multiplication to the in-phase signal and the quadrature signal input from the combiner with a second oscillation signal to which a second frequency shift opposite from the first frequency shift is applied;
• and
• digitally demodulating the in-phase signal and the quadrature signal of a baseband frequency acquired by the complex multiplication.

A wireless communication method executed by a wireless communication apparatus including a plurality of antenna elements, the wireless communication method comprising:

• generating an in-phase signal and a quadrature signal;
• distributing the generated in-phase signal to the antenna elements, and distributing the generated quadrature signal to the antenna elements;
• and
• generating a transmission signal of a radio frequency to be transmitted from the respective antenna elements by performing quadrature modulation on the distributed in-phase signal and quadrature signal, wherein
• the generating the transmission signal includes
• applying a first frequency shift according to a transmission beam direction to a first oscillation signal that is used for frequency conversion into the radio frequency, and
• the generating the in-phase signal and the quadrature signal includes
• digitally modulating transmission data to generate the in-phase signal and the quadrature signal, and
• performing complex multiplication to the generated in-phase signal and the generated quadrature signal with a second oscillation signal to which a second frequency shift opposite from the first frequency shift is applied.

A wireless communication method executed by a wireless communication apparatus including a plurality of antenna elements, the wireless communication method comprising:

• generating in-phase signals and quadrature signals of an intermediate frequency by performing quadrature demodulation on reception signals in the respective antenna elements;
• combining the in-phase signals generated in the respective antenna elements and combining the quadrature signals generated in the respective antenna elements;
• and
• acquiring reception data from the combined in-phase signal and the combined quadrature signal, wherein
• the generating the in-phase signals and the quadrature signals includes
• applying a first frequency shift according to a reception beam direction to a first oscillation signal that is used for conversion into the intermediate frequency, and
• the acquiring the reception data includes
• performing complex multiplication to the combined in-phase signal and the combined quadrature signal with a second oscillation signal to which a second frequency shift opposite from the first frequency shift is applied;
• and
• digitally demodulating the in-phase signal and the quadrature signal of a baseband frequency acquired by the complex multiplication.