Design of Indoor Positioning System Based on IEEE 802.15.4a Ultra-wideband Technology

Abstract: Global Positioning System (GPS) has revolutionized the way we navigate and get location-based information in the last decade. Unfortunately the accuracy of civilian GPS is still remaining in meter level and it does not work well in indoor environment, which is a major drawback for applications such as autonomous vehicle, robot machine and so on. UWB (Ultra-wideband) is one of the most promising technologies to solve this problem. The UWB technology has large bandwidth and it is quite robust to fading and multipath effect. Therefore, it is capable of high accuracy down to centimeters for positioning in both outdoor and indoor scenarios.  The IEEE 802.15.4a was released in 2007, which adopted UWB in this standard and specified its physical layer for accurate positioning in WPAN (Wireless Personal Area Network). Apart from the capability of accurate positioning, solutions based on this standard will have quite low power consumption and low cost.  In this thesis work a positioning system based on IEEE 802.15.4a has been designed. A few practical constrains have been taken into account in designing the system, such as performance, cost, power consumption, and governmental regulations and so forth. To reduce the system complexity and communication channel occupancy, TDOA (Time Difference of Arrival) has been chosen as the ranging protocol. The system has been designed accordingly. Main components have been selected and PCBs (Printed Circuit Board) has been designed as well. The design work covered both hardware and software. The proposed system is believed to be able to achieve a positioning accuracy of ±20 centimeters.