Target positioning method based on robust TOA/RSS in non-line-of-sight environment

Abstract

The invention discloses a target positioning method based on robust TOA / RSS in a non-line-of-sight environment. The method comprises the following steps: carrying out approximate transformation on a measurement model of an RSS measurement value and a measurement model of a TOA measurement value; obtaining a non-convex positioning problem according to the two approximate expressions by adopting a robust least square criterion; combining the maximum value of the function about the non-line-of-sight error during RSS measurement and the maximum value of the function about the non-line-of-sight error during TOA measurement, and introducing a slack variable and an auxiliary variable to obtain an equivalence problem of the non-convex positioning problem; a second-order cone relaxation method is adopted, and the equivalence problem of the non-convex positioning problem is converted into a second-order cone programming problem; solving the second-order cone programming problem by adopting an interior point method to obtain a position estimation value of the target node in the reference coordinate system; the method has the advantages that two kinds of measurement information of the received signal strength and the arrival time are fully utilized, and a global optimal solution can be obtained, so that the target positioning accuracy is greatly improved.

Description

technical field [0001] The invention relates to a target positioning technology, in particular to a target positioning method based on robust TOA (time of arrival) / RSS (received signal strength) in a non-line-of-sight environment. Background technique [0002] Target positioning technology plays a pivotal role in many applications, such as emergency response, target tracking, navigation and aviation applications. The commonly used target positioning strategy generally determines the position of the target node according to the distance measurement value. By using different hardware devices, the distance measurement value can be extracted from the characteristics of the transmitted signal transmitted by the target node to the anchor node, including time of arrival (TOA), time difference of arrival (TDOA), Angle of Arrival (AOA), Received Signal Strength (RSS). Recently, in order to further improve the target localization accuracy, more and more target localization schemes st...

AI Technical Summary

Problems solved by technology

For example: NLOS error mitigation for TOA-based localization via convex relaxation (NLOS error mitigation for TOA-based localization via convex relaxation based on convex relaxation TOA positioning non-line-of-sight) disclosed in IEEE Transactions On Wireless Communications (Institute of Electrical and Electronics Engineers (IEEE) Wireless Communications) by G.Wang et al. Error suppression method), which uses two relaxation methods of positive semi-definite relaxation and second-order cone relaxation to transform the non-convex positioning problem into a convex problem, and solve it by the interior point method. However, experiments show that the positioning performance of this method still has room for improvement.

Another example: Target localization in NLOS environments using RSS and TOA measurements disclosed in IEEE Wireless Communications Letters (Institute of Electrical and Electronics Engineers (IEEE) Wireless Communications Letters) by Slavisa Tomic et al. research), which treats all links as line-of-sight (LOS), then applies an alternating optimization method, and iteratively improves the position estimate and the average non-line-of-sight error estimate, but this method is difficult to find the global optimal solution , will lead to poor target positioning accuracy

Images