A Highly Robust and Accurate Triangle Centroid Locating Method

Abstract

The invention relates to a high-robustness and high-precision triangle centroid location method. The method comprises the following steps of searching three WiFi base stations used for location to obtain RSSI (Received Signal Strength Indicator) values of the three base stations; smoothly collecting the RSSI values by utilizing a mean smoothing method; substituting the smooth RSSI values into a polynomial obtained by fitting in order to obtain an environmental factor compensating factor EF; substituting the environmental factor compensating factor EF into a distance calculation formula: d=10^((ABS(RSSI)+EF-A) / (10*n)) in order to obtain distances d1, d2 and d3 between a locating point and the three base stations, wherein A is an average absolute value of received signal energy in 1 m, n is a signal energy attenuation coefficient, and RSSI is a value obtained after mean smoothing; and completing location by utilizing a centroid algorithm based on Euclidean according to the distances d1, d2 and d3 between the locating point and the three base stations. According to the method, the robustness and the precision can be improved.

Description

Technical field [0001] The present invention relates to the technical field of indoor positioning based on WiFi, in particular to a triangular centroid positioning method with high robustness and accuracy. Background technique [0002] Indoor positioning systems are currently one of the hot spots in the field of information technology. With the rapid development of the Internet of Things and wireless communication technologies, location-based services have shown broad application prospects in the fields of medical and health, public safety, and industrial production. Especially in the fire rescue scene, an excellent indoor positioning system can ensure the safety of firefighters, and decide the best rescue route in the shortest time to implement rescue. [0003] The Global Positioning System (GPS) is a widely used positioning technology at this stage, and it is commonly used in various location services. However, the GPS positioning system cannot perform positioning indoors, becau...

AI Technical Summary

Problems solved by technology

[0014] The principle of the triangle centroid positioning algorithm is simple, and it seems easy to implement. However, due to the diversity and complexity of environmental factors, the algorithm has great limitations in practical applications, and the robustness and positioning accuracy need to be improved.

[0015] Robustness: Due to the influence of noise, the signal will attenuate during the propagation process, and the signal attenuation models are different under various environmental factors. In some special cases, with three base stations as the center of the circle, the distance converted from the RSSI value is Three circles with radii cannot be formed as attached figure 1 For the triangle shown in , the three circles do not intersect (see figure 2 ) and the case where the intersection cannot form a triangle (see image 3 ), so that the triangle centroid location algorithm cannot be used

[0016] Positioning accuracy: Due to the interference of indoor environmental factors: such as signal multipath, reflection, absorption of walls and doors, etc., the traditional distance calculation formula can only satisfy theoretical calculations, but cannot adapt to the diversity of the environment, resulting in a decrease in positioning accuracy

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