Communication device for performing beamforming and operating method thereof

An operating method of a communication device for providing a beamformed transmission signal to a plurality of terminals, the operating method comprising:

• generating a precoding signal by precoding transmission data corresponding to each of the plurality of terminals based on a precoding matrix;
• and
• based on a beam selection matrix for selecting a portion of antennas from among a plurality of antennas, generating a transmission signal corresponding to each of the portion of antennas,
• wherein
• the transmission signal corresponding to each target terminal is constructively interfered by an interference vector corresponding to another terminal in a transmission signal component and has an amplified strength, and
• the transmission signal includes a target terminal vector, which is a transmission signal component corresponding to the target terminal, and the interference vector, and a signal of the target terminal vector is constructively interfered by the interference vector.

A communication device comprising:

• a plurality of antennas each configured to output a beamformed transmission signal to a plurality of terminals;
• a radio frequency (RF) chain arranged in a number less than a number of the plurality of antennas;
• and
• a processor configured to determine a beam selection matrix and a precoding matrix based on an area restriction condition and a beam selection condition for each of the plurality of terminals, the area restriction condition being defined such that a strength of a transmission signal with respect to each of the plurality of terminals is amplified based on constructive interference generated from another terminal among the plurality of terminals,
• wherein the transmission signal is generated by the beam selection matrix and the precoding matrix, the strength of the transmission signal being amplified based on the constructive interference by an interference vector corresponding to the other terminal.