Radio Direction-finding And Location Research In The Radio Monitoring

With the rapid development of radio communication service, to ensure the normal andeffective use of spectrum resources, the radio monitoring technology has been more widelyused. Radio direction-finding and location as the key technology plays an important role insignal detection, the source of interference finding and determination of the location of thesignal source. When a station has detected an interference signal, two fixed stations areconnected through the network to locate the signal source. And how to choose a collaborativestation to determine the specific coordinates of the signal source by the intersection of lines isvery important.Radio location is an important means of radio monitoring. Radio location technology isto use two or more observation platforms, and the stations don’t transmit signals actively, butjust passively receive the information from emitters to find out the position. Based on thesignal metrics, radio location can be divided into AOA (angle of arrival), TOA (time ofarrival), and TDOA (time diference of arrival), FDOA(frequency difference of arrival) andjoint location, etc. Currently, the radio location based on angle-of-arrival (AOA) is mainlyused. There are several factors affecting the accuracy of this positioning method, accuracy ofAOA, accuracy of map, the algorithm of radio location and selection of collaborative station.Radio monitoring network has been basically completed, the accuracy of AOA is affected byradio monitoring equipment and surrounding electromagnetic environment, and the map ofradio location generally use existing map of the city, so both of these factors are inherent inthe system error. The intersection positioning algorithm has been studied quite mature, and itcan be divided into two-dimensional plane and space intersection positioning. The final factoris related with the algorithm of station selection which is provided by our radio locationsystem, and the article effectively improves the positioning accuracy by selecting thereasonable stations.In this article, Gaussian distribution density function is applied to the model of radiodirection finding and radio location, and we study a number of practical problems of radioposition accuracy in the two-dimensional plane. The main contents are as follows:Firstly, we list the initial assumptions used for creating the model, in order to make theangle of arrival (AOA) obey the Gaussian distribution density function. Then we build themodel of one station positioning accuracy and extend the Gaussian distribution density function.Then model of two-station positioning accuracy is build by product formula of independentevents, and we do a theoretical analysis of the positioning accuracy and the validation of the numerical experiments. We have obtained some valuable theoretical results, and have beensuccessfully applied to actual projects.Secondly, we build the model of the distribution of the monitoring stations. Positioningperformance related with the position of the stations, selecting the reasonable stations caneffectively improve the positioning accuracy.Finally, we analyze station selection of radio direction-finding and location in the actualproject, and the practical application of the project shows that the effectiveness of the method.