Study On Indoor Location Algorithms For Pervasive Computing

The concept of pervasive computing was first emerged in nineties in the twentieth century. It was considered as the next information revolution which will make profound changes to people's life style. The main objective of pervasive computing is to provide service to people anywhere and at any time. In order to provide appropriate service to people, it is necessary to obtain people's information including the location information. Therefore, it is a very important research topic to obtain accurate location of an individual. GPS and cell network wireless location technology can provide good service for outdoor people, but not the case for indoor people. This paper mainly deals with pervasive computing in indoor location.At the beginning of this thesis, the concepts of pervasive computing, its research status, and its development trend are introduced. The technology and algorithm of wireless location, and their applications are addressed. The characteristics of indoor wireless communication are also analyzed. In addition, the ultra wide bandwidth signal, which is usedwidely in indoor location because of its fine time resolution, is introduced. Then, an algorithm based on correlation computing is proposed to detect Line of Sight (LOS) signal. The performance of this algorithm in correlated noise and noise with unknown parameters is analyzed and discussed.On the basis of detecting the LOS path signal, the signal information such as TOA, AOA can be used to determine the accurate location. In order to obtain the high accuracy of the location information, the data fusion model and algorithm mixing method are employed in this thesis. A new enhanced data fusion model is proposed. The simulation results show that these models are effective in promoting the location accuracy.In indoor location, the existence of None Line of Sight (NLOS), which makes LOS path signal inaccessible, causes significant deterioration in location accuracy. The source and influence of NLOS are described in details and an algorithm to reduce or eliminate the influence of NLOS is proposed. The simulation results show that the proposed algorithm can improve the accuracy regarding the affection of NLOS.Based on the accurate indoor location information, a service model is proposed to provide service to people. The techniques required to implement a system based on the model are introduced. Finally, the market expectation of the system is analyzed.It is concluded the algorithm proposed this paper could give accurateindoor location information and then provide good service for indoor situation.