A fast calibration and testing method for large-scale phased array

In order to solve the problem of long time consuming during the calibration and scanning patterns testing of large-scale phased arrays, a fast-testing method and a verification circuit is proposed in this paper. This method no longer requires the use of expensive vector network analyser (VNA), but uses a lower cost downconverter and sampling board. The downconverter converts the received RF signal into a lower IF signal, then samples and calculates the amplitude and phase of the IF signal using the sampling board. The proposed method is used to calibrate a SATCOM phased array of 1024 channels. After calibration, the RMS value of phase residual errors is less than 2°, and the RMS value of amplitude residual errors is less than 0.26dB. The calibration time using this method is about 2.2 s, while the time using traditional VNA is about 248.7 s. Compared with the traditional testing methods, this design method can significantly reduce the time and cost of measurement, which is very suitable for the testing of large-scale phased arrays. In addition, the proposed method can also be used as a basic step for other further performance tests to improve test efficiency.