Antenna system, RF communication device, and method of operating the same

An antenna system, the antenna system comprising:

• an antenna array comprising one or more sub-arrays of antenna elements in which at least one sub-array being operable in more than one state;
• and
• a state switching circuit electrically coupled to the at least one sub-array and configured to drive the at least one sub-array to operate in a first state in which an upper side lobe of the antenna array is suppressed for a first beam tilting range or in a second state in which the upper side lobe of the antenna array is suppressed for a second beam tilting range which is different from the first beam tilting range;
• wherein the state switching circuit comprises:
• a bias-T has a first terminal electrically coupled to a driver integrated chip (IC) to receive a control signal from the driver IC, a second terminal electrically coupled to a transceiver to receive/transmit a radio frequency (RF) signal from/to the transceiver, and a third terminal electrically coupled to a first terminal of a phase tuning circuit to communicate the control signal and the RF signal with the phase tuning circuit;
• and
• the phase tuning circuit having a first terminal electrically coupled to the third terminal of the bias-T and one or more second terminals electrically coupled to each of the antenna elements of the at least one sub-array, respectively,
• wherein the phase tuning circuit is configured to tune the phase of the RF signal, which passes through the phase tuning circuit, based on the control signal.