Design And Implementation Of A New Indoor Wireless Location Algorithm Based On Fingerprint Database

Indoor location system is a new concept from the development of social activities and practicability such as indoor guidance, indoor commercial activities, social network and so on. Compared with outdoor location system that has been developed for a long time, indoor location system has its limitations in location environment, location accuracy and performance of the system. In the recent years, in order to overcome the limitations of indoor location technology, indoor location attracts a lot of attention in the location field. A nature and stable indoor location system promotes the development of human society in the future.The limitation of several popular indoor location systems is in the following aspects: Firstly, the complex indoor environment, the layout and material of the walls in buildings, and activities of human beings have influence on the transmission of wireless signal, which results in the error of the whole system. Secondly, advance arrangement of experimental environment is necessary for the popular indoor location technology. For example, the signal receivers of radio frequency and Bluetooth are necessary for the indoor location system used with RF and Bluetooth technology, which adds the operation cost of the system. In the end, the nature indoor location systems often have a good performance on static location points, and it is not the same as the moving points. These limitation problems of indoor location system need to be solved in the research field.Based on the new and popular indoor location system and technology and combined with th=; feature of experiment environment, a new indoor wireless location algorithm based on Wi-Fi signal strength and fingerprint database is provided by this paper. Meanwhile, we apply this algorithm into our indoor location system successfully. In order to reduce the influence of the indoor environmental change on the location accuracy, this paper proposes relative Wi-Fi signal strength instead of absolute Wi-Fi signal strength to construct fingerprint database. The use of Wi-Fi signal is very popular in the current indoor location research. We use Wi-Fi signal as the location data, which can reduce the cost of RF and Bluetooth. In addition, this paper also proposes an effective location error correction technology, which determines whether the result is correct through tracking the location points. This technology reduces the location error greatly and improves the performance of indoor location system.