Research On WCDMA Network Localization Algorithm

With the third-generation (3G) mobile communications development and promulgation of the provisions of the U.S. E911, cellular network mobile station (MS)wireless location technology has been more and more widely watched. The service can provide information about the location of the mobile station. Therefore, in many fields has important applications, such as network optimization, entertainment, emergency and national security. Meanwhile, the wireless propagation channel in turn determines the complexity of cellular location technology will face many difficulties. How to improve the positioning accuracy to better serve the public has become the international focus on research in related fields.The full name of WCDMA Wideband CDMA, also known as CDMA Direct Spread, intended for the wideband code division multiple access, which is based on the GSM network developed 3G technology standard, is Europe's wideband CDMA technology. It has a high spreading gain, the development of larger space, the strongest global roaming capabilities, technical maturity of the best. It wideband pseudo-random (PN) sequence to differentiate between users. Different users sharing the frequency and time, improve resource utilization. Therefore, this paper WCDMA cellular network, using time of arrival/ time difference (TOA/TDOA)positioning methods to improve the mobile station positioning accuracy as the goal, from passive positioning point of view, the positioning performance parameters, affect the positioning accuracy of the factors, TDOA Location The way a variety of algorithms, non line of sight (NLOS) environment, the positioning algorithm-depth study of several aspects of cellular mobile wireless location technology.Firstly, the theoretical analysis and data support on the basis of clear technology roadmap and research content. Paper briefly discusses the positioning algorithmused qualitatively compare their performance; a detailed analysis of the characteristics of WCDMA cellular radio network, established a mobile station positioning error sources; summarizes the cellular location technology at home and abroad Research Status; and then through a comprehensive analysis to determine the research methods and priorities.Secondly, in-depth study of TOA and TDOA algorithms algorithms, the structures of the WCDMA simulation platform, respectively, LOS and NLOS TOA algorithm to simulate the two cases of the four TDOA positioning algorithm under the simulation, by changing the number of base stations To observe the change in location error variance.