Research On The Navigation Via Signals Of Opportunity System Critical Technologies

Navigation via signals of opportunity(NAVSOP)is a mean of realizing navigation using broadcast,television,cellular networks,and other types of radio signals,has the characteristics of low cost,all-weather,full range of coverage.Not only can this system work independently,but can be combined with existing navigation systems to provide higher performance navigation and positioning services.In this paper,the navigation via signals of oppotunity is used as the research object,through analyzing various types of signals characteristics and distance positioning methods,trying to provide some reference for the develop and build of ourself's NAVSOP system.The main content is as follows:1.Introduced the development background and history of the NAVSOP technology,summarized the development status and research progress at home and abroad,and expounded the basic principle of NAVSOP.2.Studied the range location method based on FM,DFM,DTMB,WCDMA,CDMA2000 and TD-SCDMA,and analyzed the positioning accuracy and error sources.A method of parameter estimation for FM propagation prediction model is proposed,and the RSSI distance finding method based on FM is further studied.The method of generating pseudo-random sequences in the other five kinds of digital signal structures is analyzed,the pseudo-random code ranging and location method based on the radio frame of digital signals is studied.3.Designed a way to realize the NAVSOP system.Analyzed the signal structure and the distribution of the base stations of the typical opportunity signals,designed the multi-source signal location process according to the characteristics of the opportunity signal,and studied the signal acquisition,selection and joint positioning.The software radio platform is used to receive the signal,the analytic hierarchy process is used to select the signal with the base station geometric distribution,signal power,measurement accuracy and other parameters in the practical application background.and finally the multi-source signal joint location model is established.The simulation results show that the system can realize the positioning and the precision in the typical condition is 30 meters.4.Analyzed the electromagnetic compatibility problem of the opportunity signal navigation system.Combining the theory of electromagnetic compatibility and GNSS compatibility,the connotation of electromagnetic compatibility of NAVSOP system is given.At the end of the NAVSOP system,the useful signal-to-noise ratio is attenuated to the electromagnetic compatibility evaluation index to studied the interference degree from other signals to the useful signal Finally,the DTMB,WCDMA,CDMA2000 and TD-SCDMA in the joint positioning of multi-source signals are validated,and the suggestions for further research and development of the NAVSOP system are given.