User equipment and base station configured to perform beamforming and operating methods thereof

A base station comprising:

• an antenna array configured to
• simultaneously form a first horizontal beam and a second horizontal beam with a same frequency band during a first time period, or
• form at least one horizontal beam with different frequency bands during the first time period;
• and
• processing circuitry configured to
• transmit a signal using
• double beams including the first horizontal beam and the second horizontal beam, or
• the at least one horizontal beam;
• and
• first determine a horizontal tilting angle of each of the first horizontal beam and the second horizontal beam based on a first K-mean clustering algorithm, the first K-mean clustering algorithm including
• signal-to-interference-plus-noise ratios (SINRs) of the first horizontal beam and the second horizontal beam as an objective function, and
• inter-beam interference (IBI) between the first horizontal beam and the second horizontal beam as a variable of the objective function, or
• second determine a horizontal tilting angle of each of the at least one horizontal beam based on a second K-mean clustering algorithm having an SINR of the at least one horizontal beam as an objective function.

An operating method of a base station, the method comprising:

• forming beams, the forming of the beams including
• simultaneously forming a first horizontal beam and a second horizontal beam with a same frequency band during a first time period, or
• forming at least one horizontal beam with different frequency bands during the first time period;
• transmitting a signal by using
• double beams including the first horizontal beam and the second horizontal beam, or
• the at least one horizontal beam;
• and
• performing a first determination or a second determination, the first determination including determining a horizontal tilting angle of each of the first horizontal beam and the second horizontal beam based on a first K-mean clustering algorithm, the first K-mean clustering algorithm including
• signal-to-interference-plus-noise ratios (SINRs) of the first horizontal beam and the second horizontal beam as an objective function, and
• inter-beam interference (IBI) between the first horizontal beam and the second horizontal beam as a variable of the objective function,
• and the second determination including determining a horizontal tilting angle of each of the at least one horizontal beam based on a second K-mean clustering algorithm having an SINR of the at least one horizontal beam as an objective function.