Design And Implementation Of An Indoor Positioning Node Based On Wireless Sesor Network

With the widespread of wireless networks and development of mobile computing technology, people become increasingly strong interest in location-aware. Wireless Sensor Networks (WSN) and Location-ased Services (LBS), gradually come into people's lives. Especially when the United States put forward the strategy of "Smarter Planet", and our government supports Internet of Things technology strongly, WSN and LBS show great vitality in the field of individual applications, public services, city management and so on. It has quickly become the focus of attention and the hot research topic in the world.Nowadays, the outdoor positioning technology has already been quite sophisticated. It can satisfy the requirements of outdoor positioning. Although both indoor positioning technology outdoor positioning technology are used to locate the positon of the target object, indoor positioning technology has its own complexity and special requirements. Indoor positioning technology still has many deficiencies in terms of cost, performance and application, thus limiting the popularity of location-based services. So indoor positioning is a prerequisite and key to implement the location-based services in indoor environment.This dissertation has completed the design and implementation of an indoor positioning node based on WSN. The sensor node uses the highly intergrated, ultra-low power SoC chip GS1011 as the main controller. Its hardware design has realized the power supply module, wireless network transmission module, serial communication module and various sensors. The software design of this sensor node is based on uVelOSity embedded real-time operating system. This sensor node has realized the functionalitise that enable it to associate into certain network, scan received signal strength indicator (RSSI) of the access points (AP) in the indoor environment, and transfer the data to the server.By using the indoor location estimation algorithm based on fingerprinting, the server estimates the location of the node with the distribution of RSSI. Moreover, the server can provide the sensor node the information services such as temperature, humidity, light strength and acceleration, etc. Also the design of low power consumption is taken into consideration by using the means of periodic sleep and motion detection based on acceleration sensor.