The Analysis And Research On Anti-interference Of VHF Radio

With the rapid development of the global economy,people life is getting faster and faster,the use of air transport costs reduced gradually,aviation has become an important part of the transportation industry,it also contributed to the rapid development of aviation industry in China.As the principal means of communication between the airplane and the ground,VHF ground-to-air communication has also been developed rapidly.In order to ensure the safe operation of the aircraft,VHF stations and frequency are rapidly increasing,which leads to the increasing probability of interference of VHF radio.In this paper,we analyse the VHF radio stations used in the ATC system and the problems experienced in practical work.Through the analysis combined with the problems in the practical work,this paper studies how to improve the anti-jamming capability of radio stations.We can change the setting of radio stations and parameters and adjust the filter parameters.The study provides reliable security for VHF ground-to-air communication,and also provides a theoretical basis for building new airport VHF radio stations.The structure of this article is as follows.Firstly,according to the VHF communication system utilized in local station,this paper introduces the communication principle of VHF communication and the composition of VHF communication systems.At the same time,based on the analysis of current systems interference,this paper introduces the reason and the mechanism of the radio interference in this region.Secondly,the theoretical analysis is carried out from the aspect of VHF radio.In this paper,the isolation between the antenna is computed,and the limitation of the antenna situation is analyzed.At the same time,in order to avoid intermodulation interference and adjacent channel interference,the frequency distribution of each antenna should be fixed as reasonable as possible.Based on the above theories,this paper puts forward an improvement scheme for existing problems,and then makes a verification of theoretical analysis by building experimental platform.Thirdly,we provide an improvement on the existing problem based on the basis of these theories.Through the construction of the experimental platform,we use R & S radio station to perform the theoretical analysis and makes reasonable suggestions on the verification results.Then,to improve the ability of radio to resist all kinds of interference,we can change the radio parameter setting and filter parameter adjustment,so as to prepare for the protection of interference in the actual work.Finally,at the last part of this paper,we take a summary for all the work we had done.It summarizes the theoretical and practical significance,and also talks over the shortage of the present work and the direction of future work.