Antenna element self-test and monitoring

An apparatus system comprising:

• a phased array antenna comprising an array of antenna elements, the array of antenna elements forming a plurality of antenna element pairs, each antenna element pair of the plurality of antenna element pairs including a first antenna element and a second antenna element;
• a processor system;
• a plurality of transmitter circuits, each transmitter circuit of the plurality of transmitter circuits connected to a different corresponding one of the antenna elements within the array of antenna elements;
• for each transmitter circuit among the plurality of transmitter circuits, a directional coupler connected to supply a signal to that transmitter circuit and a bidirectional coupler connected between that transmitter circuit and the antenna element to which that transmitter circuit is connected;
• and
• for each antenna element pair of the plurality antenna element pairs,
• an RF pilot signal source;
• a detector system for measuring a signal characteristic;
• a first switching system for selectively connecting signals from the RF pilot signal source for that antenna element pair to the directional couplers for the transmitter circuits connected to the antenna elements of that antenna element pair;
• and
• a second switching system for selectively connecting signals from the bidirectional couplers for the transmitter circuits connected to the antenna elements for that antenna element pair to the detector system,
• wherein the processor system is programmed to select and test each antenna element pair among the plurality of antenna element pairs, and wherein the processor system is programmed to test each selected antenna element pair by using the first and second switching systems and the detector system for that selected antenna element pair to perform one or more measurements selected from the group consisting of a return loss measurement and a cross-element gain measurement.