Communication system, apparatus and methods for calibrating an antenna array

摘要

A method for calibrating (700) an antenna array comprises a plurality of antenna elements coupled to a plurality of respective receive paths in a wireless communication system. The method comprises, in receive mode, applying a test signal to an individual single receive path (715) of the plurality of receive paths; and feeding back the test signal via a switched coupler network. The method further comprises running a receive calibration measurement routine to determine at least one measurement value used to calibrate the individual signal receive path and waiting for at least one converged measurement value; and extracting (720) the converged measurement value for at least one individual receive path. The steps of applying, running, extracting for a next individual single receive path are repeated until the calibration routine has completed (725). The method further comprises selecting a converged measurement value of at least one individual receive path from a plurality of receive paths (730) to form a reference receiver calibration result (730); normalizing a plurality of at least one measurement values of the plurality of receive paths using the reference receiver calibration result (730); and applying a normalized value to at least one of the plurality of receive paths.

主权项

1. A method for calibrating an antenna array comprising a plurality of antenna elements coupled to a plurality of respective receive paths in a wireless communication system, the method comprising in receive mode the steps of:
providing first digital IQ signals; translating the first digital IQ signals to a radio frequency to generate a receive test signal; applying the receive test signal to a switched coupler array network so that the receive test signal is substantially coupled only to an individual single receive path of the plurality of receive paths to transform the received test signal to a feedback digital IQ signal; selecting the feedback digital IQ signal; running a receive calibration measurement routine using the first digital IQ signals on at least one processor configured to determine at least one measurement value of at least amplitude, phase or latency and waiting for at least one converged measurement value, wherein the calibration measurement comprises a comparison of an adapted digital IQ signal and the selected feedback digital IQ signal on an output of the individual single receive path to determine said at least one converged measurement value; extracting the converged measurement value for at least one individual receive path; repeating steps of applying, selecting running, and extracting for a next individual single receive path until the calibration routine has completed; selecting a converged measurement value of at least one individual receive path from a plurality of receive paths to form a reference receiver calibration result; normalizing a plurality of at least one measurement values of the plurality of receive paths using the reference receiver calibration result; selecting one of the plurality of normalized measurement values based on prescribed criteria; and applying a selected normalized value to at least one of the plurality of receive paths.