System and method for adaptive correction to phased array antenna array coefficients through dithering and near-field sensing

A system for adaptively correcting the excitation or receive coefficients for a phased array antenna that comprises a plurality of antenna elements, wherein the coefficients have a magnitude and phase, the system comprising:

• one or more sensors or transmitting antennas located in the near field of the phased array antenna, the sensor sensing the phased array antenna transmission, and the transmitting antenna transmitting a signal that is received by the phased array antenna;
• a memory that stores a reference signal that represents either the sensor response to a desired phased array antenna transmission that is accomplished with predetermined excitation coefficients or the transmitting antenna transmission that results in a desired phased array antenna reception that would be accomplished with predetermined receive coefficients;
• and
• a processor that:
• modifies the magnitudes and phases of the coefficients in a predetermined manner to create a modified phased array antenna transmission or reception, wherein the modification comprises modifying the coefficients for each element of the array and wherein the predetermined manner comprises dithering the coefficients by independently fluctuating the magnitude and phase for each element of the array, wherein the fluctuations are independent from element to element,
• determines an actual signal that represents either the sensor response to the modified transmission or the phased array antenna output with the modified coefficients, and
• simultaneously corrects the coefficients for all of the elements in a manner that is based on the reference signal and the actual signal, the correction accomplished by determining an error signal based on a complex conjugation of the difference between the actual signal and the reference signal and minimizing the error signal, such that either the modified phased array antenna transmission becomes closer to the desired transmission or the modified phased array antenna reception becomes closer to the desired reception.