Systems and methods for calibrating phased array antennas

A method of handing over communications between a first communication system and a second communication system using an antenna system comprising an antenna array of at least first and second antennas, the method comprising:

• during a first portion of a handover period:
• forming a first beam for communication with the first communication system using the first antenna,
• activating a calibration circuit coupled to a calibration element;
• and
• calibrating the second antenna using the calibration circuit and the calibration element;
• during a second portion of the handover period:
• forming a second beam for communication with the second communication system using the second antenna for a handed over communication with the second communication system;
• and
• maintaining the first beam for communication with the first communication system using the first antenna;
• and
• during a third portion of the handover period:
• maintaining the second beam for communication with the second communication system using the second antenna,
• activating the calibration circuit coupled to the calibration element;
• and
• calibrating the first antenna using the calibration circuit and the calibration element,
• wherein the first beam has a similar gain as the second beam.

An antenna system comprising:

• an antenna array comprising first and second antennas;
• a calibration circuit;
• a cross-coupled switch coupled to the first and second antennas;
• and
• a controller configured to:
• during a first portion of a handover period:
• control a switching state of the cross-coupled switch to cause it to output signals communicated between the antenna system and a first communication system through a first beam formed using the first antenna, and
• command the calibration circuit to perform a calibration procedure on the second antenna using a calibration element;
• during a second portion of the handover period:
• control the switching state of the cross-coupled switch to cause it to output signal communicated between the antenna system and a second communication system through a second beam formed using the second antenna for a handed over communication with the second communication system;
• and
• maintain the first beam for communication with the first communication system using the first antenna;
• and
• during a third portion of the handover period:
• maintain the second beam for communication with the second communication system using the second antenna, and
• command the calibration circuit to perform a calibration procedure on the first antenna using a calibration element,
• wherein the first beam has a similar gain as the second beam.