Calibration of a low-cost 8x8 active phased array antenna

This paper presents the calibration process involved in a planar active phased array antenna operating in the K-band (17.7-20.2 GHz). The array consists of eight columns, each containing a 1 x 8 subarray of patch antennas. To enhance the antenna bandwidth, a double-stacked patch structure is employed. We analyze the challenges encountered when measuring active antennas. Additionally, we discuss the solutions and calibration techniques used to improve the array performance. Finally, we present the results of the optimal calibration approach, comparing simulated and measured data, both with and without calibration, to evaluate the improvements achieved.