Research Of Indoor Wireless Positioning System Based On GPS

Global Positioning System can achieve up to98%of the global coverage.It can provide real-time global and all-weather navigation and positioning services.The system has been widely used in various fields.However,with the continuous advancement of social and economic and increasing requirements on quality of life. The development of indoor positioning can not be overlooked. Large-scale indoor environments such as libraries, museums, exhibition halls, airports, warehouses, supermarkets, hospitals, mine operations, fire scene, and want to get location information, it is difficult to achieve by the application of global positioning system. When the GPS receiver works indoor, the signal that reaches the receiver can not be avoided through the layers of obstacles. Because of signal attenuation is very serious when it meets obstacles, so the positioning accuracy is very low even not able to achieve positioning. In this case the indoor positioning technology would appear. Then a variety of indoor positioning technology and positioning methods also appear. Designed in this paper is indoor positioning system that based on5.8GHz carrier, the main is the analysis and design of receiver.The article briefly describes the indoor positioning technology of GPS, because of the shortcomings of GPS leads to other wireless indoor positioning technology. And detailed description the principle and their respective advantages and disadvantages of several indoor wireless positioning technology and positioning method. This article designed indoor positioning system that based on5.8GHz carrier, it mainly consists of transmitters, reference stations and receiver. In this paper, it give a detailed description of the design of the receiver, it is mainly composed of the RF processing and baseband processor. The purpose of the RF part is RF signal the converted to IF. It mainly consists of low noise amplification circuit, filter circuit, mixer (frequency) circuit, demodulation circuit, etc. Detailed description on the function of each part, and selected each chip in accordance with its performance, made a detailed description of the choice of chip performance and use. The purpose of the baseband processor part is to get navigation and positioning data through the digital signal processing, the most important is capture and tracking. This design uses the parallel code phase acquisition algorithm to capture signal and get the rough frequency and code phase value, using the carrier and code tracking combining the signal tracking algorithm to track the exact frequency and code phase signal captured. Then simulate the above two kinds of algorithms using the data of RF collection of GPS signal by the university of Colorado based on Matlab platform.