US Patent 11570026 Communication apparatus and communication method

Provided are communication apparatus and a communication method that allow for secure communication even in a case that an eavesdropper has multiple antennas. An apparatus includes a transmitter configured to transmit a constant amplitude signal from three or more transmit antennas; a controller configured to control a phase of the constant amplitude signal, based on channel information and a target symbol; and a modulation unit configured to generate a modulation symbol from bits. The target symbol is generated by multiplying the modulation symbol by an amplitude coefficient.