Wireless radio frequency positioning method based on Bayesian theory

Abstract

The invention discloses a wireless radio frequency locating method based on the Bayesian theory. The method comprises the following steps: readers are positioned at the boundary of an area to be monitored; a reference tag is fixed in the indoor area to be monitored in a rectangular grid form; when a radio frequency tag is arranged in an object to be monitored, and the object is positioned in the area to be monitored, the readers transfer the radio frequency signal intensity of the reference tag and the object tag to be monitored to a host computer; the host computer compares the absolute differences of the radio frequency signal intensity of the reference tag and the tag object to be monitored for determining the recent reference tag near the object to be monitored and obtaining the reference position of the object to be monitored; then, the host computer obtains the distance information between the tag object to be monitored and each reader; and finally, the host computer carries out data fusion to the obtained positional information based on the Bayesian theory, thereby obtaining the position coordinates of the object tag to be monitored. By dint of the method, a positioning system has good flexibility and adaptability in restraining the noise interference, and has good precision and real-time performance in the position inductive aspect.

Description

technical field [0001] The invention relates to a wireless precise positioning method, in particular to a wireless radio frequency positioning method based on the signal strength value of a radio frequency identification tag in the field of indoor precise positioning. Background technique [0002] Wireless positioning technology processes certain parameters of the received electromagnetic waves through specific algorithms to infer the position of the object to be measured. The measurement parameters include the transmission time, amplitude, phase, angle of arrival and signal strength of the test signal. At present, with the continuous development of wireless technology, mobile computing devices and the Internet, indoor positioning service systems have attracted more and more attention. The commonly used indoor wireless positioning technologies are: [0003] (1) Indoor GPS positioning technology: GPS is currently the most widely used positioning technology. However, when t...

AI Technical Summary

Problems solved by technology

However, when the GPS receiver works indoors, because the signal is greatly attenuated by the influence of buildings, its positioning accuracy is very low, the positioning speed is relatively slow, and the cost of the locator terminal is high

[0004] (2) Cellular positioning technology: Cellular networks such as GSM and CDMA all support positioning technology, but factors such as non-line-of-sight propagation, multipath effect, and multiple access interference reduce its positioning accuracy, and involve user privacy issues, making its promotion restricted. certain restrictions

[0005] (3) Infrared technology: Active tags based on diffuse infrared technology can be used for indoor positioning, but it requires that the object to be tested must be in a straight line with the infrared reader, and the positioning distance is too close, so the practical application is of little significance

The system applying this kind of technology is easy to build, but the measurement accuracy is not satisfactory and needs to be further improved

[0007] (5) Ultrasonic technology: At present, the successful use of this technology can indeed achieve high positioning accuracy, but it requires a large amount of infrastructure support, the cost is expensive, and it cannot be widely promoted

The cost of current readers is relatively high, and most of them can only work at a single frequency point

Images