Research Of Indoor Wireless Location Algorithm Based On RSSI

In this paper, it firstly introduces the wireless positioning technology,RFID technology and RFID system in detail. The commonly used algorithms of TOA、TDOA 、 k NN are deduced in theory, and characters of each algorithm are expounded in detail.It introduces the theory of LANDMARC and VIRE positioning algorithms and makes a performance analysis of the LANDMARC and VIRE. The average position accuracy of LANDMARC is 1.3 meters, but the average position accuracy of VIRE is 0.5 meters through the simulation experiments. Then focusing on the above algorithms done the following research: first, we analysis the rectangular structure which composes of reference tags from probability and geometric based on LANDMARC algorithm and put forward the triangle structure which composes of reference tags. Triangle structure makes the average positioning accuracy of the algorithm up to 0.6 meters. Secondly, non-linear polynomial interpolation method is Introduced in VIRE which makes the average positioning accuracy up to 0.42 meters; then virtual tag method is applied to boundary which can control the positioning error of boundary tags in 0.5 meters, and the average precision can reach 0.27 meters. Finally, virtual tag method is applied to the triangle structure, however, the system average positioning accuracy only reaches 0.32 meters, but the position error of center tags can be controlled in 0.2 meters when we can reduce the number of reference tags.In summary, the simulation results show that the position accuracy and stability of improved algorithm based on VIRE and LANDMARC have been significantly improved.