Research On KU-Band Phased Array Technology Based On Vector Control

With the continuous development of wireless communication technology,antennas,as important components of communication and radar systems,face many development opportunities and technical challenges.Among them,array antennas have become a necessary choice to meet special needs,such as broadband,high gain,low crosspolarization,and multi-beam.However,traditional array antenna designs often face challenges in achieving ultra-low side-lobe directional patterns,such as the high hardware cost brought by array antenna synthesis.Therefore,design solutions such as envelope random optimization algorithms,adaptive array antennas,and metamaterial antennas have gradually been applied in array antenna synthesis.Among them,time modulation technology has developed rapidly.By using time domain design variables,system hardware complexity is greatly reduced,design flexibility is improved,and it has been widely used in phased array antenna design.However,there are still problems with implementing amplitude and phase control,such as the hardware cost of phase shifters.Therefore,a new theory based on vector control technology needs to be established for amplitude and phase control to achieve high-precision and low-cost beam scanning.This article focuses on this starting point and emphasizes research on vector control methods.Based on the analysis of cyclic modulation theory and the amplitude and phase mapping relationship between modulation signals and radio frequency signals,the basic theory of amplitude and phase integrated control is established and improved.Based on the 2-bit modulation pulse,the time-domain mathematical representation function and the amplitude and phase mapping relationship of the frequency-domain radio frequency signal are analyzed,and an ideal mathematical model is proposed.At the same time,based on the factors that may cause vector control accuracy errors in actual engineering,such as the phase and amplitude imbalance of modulation devices and the non-ideality of radio frequency switches,the impact law on vector control accuracy is calculated and analyzed,and this control theory is improved.A correction model for non-ideal factors is proposed,and its validity is verified through simulation.Meanwhile,this article also conducted design work on a vector-controlled array prototype,proposed an overall architecture based on power distribution networks,beam control circuits,and array radiation surfaces.The design of the actual 2-bit modulation circuit is carried out from device selection,structural design,and board diagram design.By testing the actual radio frequency signal waveform and statistically analyzing its nonideal characteristics,two experiments were conducted.First,a static amplitude output test was conducted to preliminarily verify the performance of the vector control module,test and debug its output amplitude and achieve the required design accuracy for amplitude control.The second experiment was a far-field radiation pattern test of the array prototype,which conducted comprehensive experimental tests on beam scanning capability,operating frequency band,and side-lobe level,aimed at verifying whether the vector control module and vector control method can be practically applied in phased array antenna design.Finally,the feasibility and effectiveness of this method were verified.