Research On Thinned Phased Array Antenna Synthesis And Its System Design

Phased array technology has been steadily evolving with advances in solid-state microwave integrated circuits,analysis and design tools,and reliable manufacturing practices.Phased array antennas can be divided into passive phased array antennas,active phased array antennas and digital phased array antennas according to the type of feed.The next generation of phased arrays will use a high level of digitalization,which will achieve extensive improvements in capability and performance,but currently the mature and widely used technology is active phased array.Active phased arrays use digital phase shifters to achieve beam scanning,but with the increase in the size of the array,the number of active modules used increases dramatically making the cost of the system increases dramatically.At the same time,high radiation gain and low subflap level are often required in array antennas to improve the signal-to-noise ratio.Thinned phased array design is an effective way to reduce system cost and achieve low partials level.Compared to uniform arrays,thinned arrays have the same array size and fewer excitation units,achieving the same performance while significantly reducing the cost and power consumption of the system,so thinned array design is imperative.Array synthesis of thinned design is a nonlinear optimization problem,a fast computational depth optimization of thinned array synthesis algorithm has been the research hotspots of scholars in various countries.In this thesis,I focus on the thinned design of active phased array antenna system,from efficient thinned array synthesis algorithm and thinned phased array systematic design implementation respectively,the main research contents are as follows.1.JAYA-IFT(JAYA-Iterative Fourier Technique)algorithm is used to synthesize thinned arrays.In this thesis,I study the nature and principle of fast convergence of the IFT algorithm in thinned array synthesis.The IFT algorithm has efficient computation but it is easy to fall into local convergence,and it is often difficult to find lower peak subflap levels;I study the principle of the JAYA algorithm,the new iteration direction is updated randomly toward the optimal individual,and the thinned array synthesis is based on the principle of the JAYA algorithm,and I find that the algorithm has strong global search capability,but the computational efficiency is very low and convergence is slow.The JAYA-IFT algorithm is proposed to combine the advantages of the two algorithms,and the new algorithm has a faster convergence speed and a stronger depth optimization capability,and the synthesized peak subflap level is better than the existing references.2.A 8×8 thinned phased array antenna active system is designed,and the proposed JAYA-IFT algorithm is used to synthesize the excitation distribution of 75% fill rate for antenna simulation.The transmit digital phase shift module,power distribution circuit,beam control circuit,etc.are designed to realize a complete set of thinned phased array antenna.Reasonable analysis and actual measurement of each module,the effect is relatively satisfactory and within the acceptable range.3.I Design a set of FPGA-based beam control system,program each working state of the control system,calculate the beam scanning control code,finally complete the calibration of the transmitting module,combine with the active antenna to complete the system directional map scanning test,EIRP test,etc.,and finally realize a set of transmitting phased array antenna system.