Phase measuring circuit of phased array antenna

A phase measurement circuit of a phased array antenna having both transmitting and receiving functions and having a transmission frequency band and a reception frequency band of different frequencies, comprising:

• a plurality of antenna elements arranged in an array;
• phase shifters disposed corresponding to said antenna elements, respectively, for shifting phases of signals to form a beam in a desired direction by changing the phase value;
• a control circuit for controlling the phase shift quantity of said phase shifter;
• a test antenna for receiving electromagnetic waves in the transmission frequency band from the phased array antenna and transmitting a test signal for measuring an excitation phase to each element of the phased array antenna;
• and
• a test translator for converting the frequency of the electromagnetic waves of the transmission frequency band received by the test antenna to that of the electromagnetic waves of the reception frequency band and outputting the converted signal as a test signal to the test antenna, in which one of the element antennas of the phased array antenna functions as said test antenna, and said test translator is incorporated in the phased array antenna.

A phase measurement circuit of a phased array antenna having both transmitting and receiving functions and having a transmission frequency band and a reception frequency band of different frequencies, comprising:

• a plurality of antenna elements arranged in an array;
• phase shifters disposed corresponding to said antenna elements, respectively, for shifting phases of signals to form a beam in a desired direction by changing the phase value;
• a control circuit for controlling the phase shift quantity of said phase shifter;
• a test antenna for receiving electromagnetic waves in the transmission frequency band from the phased array antenna and transmitting a test signal for measuring an excitation phase to each element of the phased array antenna;
• and
• a test translator for converting the frequency of the electromagnetic waves of the transmission frequency band received by the test antenna to that of the electromagnetic waves of a reception frequency band and outputting the converted signal as a test signal to the test antenna, in which one of element antennas of the phased array antenna functions as said test antenna, said test translator is incorporated in the phased array antenna, and there is provided in the phased array antenna a switching circuit for connecting an excitation terminal of said test antenna to said test translator or to said phase shifter.