Implementation and optimization of amplitude and phase measurement based on Kalman filtering

Accurate pointing of phased array antenna beams requires precise phase and amplitude coherence among each array element channel. However, in practical phased array antenna systems, complete consistency in the amplitudes and phases of each array element channel is unattainable. Therefore, real-time monitoring and correction of amplitude and phase errors in the array channels are essential. The core of array unit calibration lies in precise measurement or estimation of channel amplitude and phase errors. This paper introduces a method for precise amplitude and phase measurement based on Kalman filtering and comprehensive phase parameter joint estimation. This approach combines Direct Fourier Transform (DFT) with direct weighted accumulation and iterative Kalman filtering. Simulation experiments demonstrate that this method significantly enhances measurement accuracy by an order of magnitude, with root mean square amplitude measurement accuracy surpassing 0.002 dB and phase measurement accuracy exceeding 0.0005°. The architecture utilizes Zynq-7000 + ADRV9009 for a compact design. By optimizing FPGA design logic, FPGA resource utilization is reduced from 36% to 26%, resulting in a decrease in power consumption from 2.17857W to 1.33948W. Through data extraction and interpolation, multiple channels can be measured simultaneously using the same algorithm module for amplitude and phase measurements. This method achieves high accuracy in phase measurement and exhibits promising engineering applications.