Research On The Protection Of Short Wave Radio Monitoring Station Under The Interference Of Differerent Electromagnetic Environment

After three"radio-five-year"plan, radio career have been developing steadily. China has built a relatively complete radio monitoring, direction finding system. With the popularization and application of radio services, the electromagnetic environment is deteriorating radio stations monitoring, direction finding capabilities are severely constrained, In particular the protection of shortwave radio stations surrounding electromagnetic environment is very important.This article analyzes the influence of the form and the impact mechanism, between the common source of radio interference such as high voltage transmission line, the frequency transmitter and ISM RF equipment and the monitoring station.Through formula derivation, solving and analysis, simulation study of graph,obtaining the protection distance between the single source of radio interference and monitoring station. One level short wave radio monitoring station electromagnetic environmental protection as an example,the layer is shown in the form of short wave radio monitoring station in Chengjiang for protection zone common source of radio interference in the end. The research results can be used for radio management department for approval in accordance with the Chengjiang shortwave radio stations surrounding the radio transmission equipment.With the rapid development of the radio service, the protection distance between the single radio interference and the monitoring station is not suitable for the protection of the existing monitoring stations.In complex electromagnetic environment, the interference signal is superimposed on each other to form a new interference signal, and enter into the receiving antenna.Through a number of intermodulation interference signals under the influence of three order intermodulation products the most serious analyses and solutions,derived three kinds of expressions of the maximum allowable strength in no less than one radio interference condition.The relationship between the maximum allowable strength and the distance protection is derived. The research results of radio station electromagnetic environment protection, provides a reliable measure that can be used shortwave radio stations surrounding electromagnetic environment analysis.