| In recent years,with the rapid progress of integrated circuit technology and signal processing technology,digital beam forming(DBF)technology has increasingly become a research hotspot at home and abroad.With the advantages of simultaneous multi-beam,large dynamic range,high real-time performance,etc.,it is widely used in communication and radar systems.At the same time,the conformal array antenna,a technical field that started relatively late in China,has attracted more and more attention.Compared with traditional linear arrays and planar arrays,conformal arrays have the advantages of larger beam scanning range and better space utilization.This article is based on the satellite-to-ground communication conformal array digital beam forming system project,The system combined satellite communications,conformal array antennas and digital beamforming together,realized digital beam scanning with large coverage.First,this article introduces the research background and significance of these key technologies,the current research status at home and abroad,and the main content arrangement of the article.Secondly,the related basic theories of conformal array and digital beamforming technology are introduced.The array signal model and beamforming principle are analyzed and simulated.The arrangement method of spherical conformal array and the antenna pattern of any array are studied,and the conformal array antenna unit,layout method and gain estimation used in the system are given.Then,this article introduces the project background and structure of the system,and focuses on the design and implementation of the signal processing system,including the calculation of satellite position and pointing angle,the design methods of conformal array digital beamforming,digital down-conversion and other technologies,as well as hardware implementation platforms,chip selection,and solutions to key technical difficulties.Finally,the relevant experiments of the system are introduced,including the performance test and calibration of the antenna,the G/T value performance test of the system,and the system function joint debugging.Through these experiments,the functional correctness of the system is verified,and the measured result of G/T value that can explain the performance of the system is given. |
