Research On Receiving Multi-beam Technology And Its Engineering Implementation

Since the 1960 s,with the increasing demand for long-range intercontinental ballistic missile detection and tracking,phased array antenna theory and practice have made considerable progress,and the development of digital computer technology has given birth to phased array radar.Digital multi-beamforming technology has become a key research direction of phased array radar technology due to its flexible beam control and ultra-low beam sidelobes.With the continuous improvement of modern digital signal processing technology,digital multi-beam forming technology also has a wide range of applications in many other fields,such as sonar,communications,and satellite antennas.In this thesis,the relevant technology of receiving multi-beam forming is studied based on the actual phased array radar project.The main research work is as follows:First,the basic principles of the array antenna and three antenna models are introduced,the basic characteristics and antenna pattern of the uniform linear array are mainly studied,and the related principles of beamforming and the digital multibeam forming method are introduced based on the uniform linear array.Then,the related principles of radar angle measurement and two commonly used radar angle measurement methods are introduced respectively,and the traditional multi-beam angle measurement method is studied in this paper.Aiming at the angle measurement error of the above methods,this paper proposes a multi-beam angle measurement method based on adjacent three beams and an iterative multi-beam angle measurement method.The comparison of simulation experiments under a variety of beam spacing and number of beams demonstrates their performance superiority compared with traditional methods.Finally,using the tools such as Vivado,ISE,the VHDL language was implemented on the FPGA hardware platform: the digital down-conversion technology was used to move the 32-channel IF signal received by the phased array radar antenna to the baseband and extracted by 4 times.On amplitude and phase errors between the 32-channel,the internal and external field corrections are completed using pulse compression technology and slant distance method.The beam-related weight data is generated by software such as Matlab,and 8 receiving beams are formed according to the control of the radar system.The analysis verified the correctness of the system due to the target trace data Obtained by UAV aircraft experiment.