Research On Electromagnetic Compatibility Technology Of Low-orbit Remote Sensing Satellites Based On Multi-frequency Interference

With the development of aerospace technology,the requirements for the electromagnetic compatibility of satellites are increasing,and the research needs are growing.At the stage of satellite design and initial research,it has become an indispensable research work in satellite development to consider and design the electromagnetic compatibility of satellites and take some technical measures in a targeted manner.Therefore,the analysis,design and test of electromagnetic compatibility of satellites are of great importance to both research and engineering application.The paper focuses on the electromagnetic compatibility of a certain type of low-orbit remote sensing satellite system as the research object,and studies the technical solutions of limiting measures of the digital transmission antenna and improving and increasing the antenna isolation;a miniaturized hairpin microstrip filter is designed and payload by using circuit filtering technology to realize the effective suppression of the out-of-band signal of the payload.After imposing the above two technical measures,the paper carried out a test pilot study.The results prove that the two technical measures have greatly improved the electromagnetic compatibility of this low-orbit remote sensing satellite system and can meet the design requirements of this low-orbit remote sensing satellite system.The main research contents of the thesis are as follows:(1)To address the possible co-frequency interference problem between this low-orbit remote sensing satellite data transmission system and the payload system,the thesis analyzes and studies the electromagnetic compatibility of the system from the spatial dimension and the frequency dimension.In the spatial dimension,the simulation and calculation of the isolation degree of the data transmission and the payload antenna under the given layout are carried out;in the frequency dimension,the out-of-band reception and in-band reception of the payload are estimated and analyzed by using the link analysis method.(2)Based on the simulation and analysis of the electromagnetic compatibility of the digital transmission system and the payload system,the electromagnetic compatibility between the two systems is tested.The interference characteristics of the interference signal to the payload reception are obtained through the wired interference mapping test.The reliability of the test and analysis is verified by obtaining the receiving spectrum characteristics of the payload through the wireless test and analysis.(3)On the basis of the above electromagnetic compatibility analysis and test of low-orbit remote sensing satellite,simulations and calculations are carried out for the antenna isolation degree of different attitudes of the star with a given antenna layout,and a solution is proposed to change the limit pointing of the digital transmission antenna to improve the isolation degree between antennas;for the problem of serious interference of the digital transmission signal to the payload,a miniaturized,low insertion loss hairpin microstrip filter that can be integrated with the antenna T/R component package is designed to further suppress the payload band interference.filter,which further suppresses the out-of-band interference signal of the payload.The system test proves that the solution is effective and can meet the electromagnetic compatibility requirements of this low-orbit remote sensing satellite system.