A Method for Improving UWB Indoor Positioning

Abstract

The existing positioning methods that use received signal strength indication (RSSI) and channel state information (CSI) may suffer from multipath and shadowing in a complex wireless environment, which can result in more positioning errors. This paper proposes a method for accurate multilabel positioning in the non-line-of-sight (NLOS) environment. First, the position is roughly estimated using the orthogonal variable spreading factor (OVSF-TH) algorithm, which can automatically match the signal interference. The ultra-wideband (UWB) spectral density and pulse amplitude in the time domain are used to determine the direction of the label and enhance estimation of the mobile label direction. Then, the location of the tag is obtained by triangulation, and a coordinate-based coordinate estimation method is proposed to calculate the relative displacement of multiple tags to determine the label position. Finally, by setting up a real experimental environment, the influence of the number of base stations on the accuracy and the performance of the localization method under different circumstances are analyzed. The theoretical analysis and experimental results show that the method is simple to deploy, inexpensive, and very accurate in terms of positioning, having a clearly effective indoor positioning accuracy. Compared with other existing positioning methods, this method can achieve more accurate positioning. Moreover, it has important theoretical and practical applicability because of the reliability and accuracy of indoor positioning in an NLOS environment.

Improving Pedestrian Safety Using Ultra-Wideband Sensors: A Study of Time-to-Collision Estimation

“…First, the authors of [22,23] mentioned that UWB measurements can be impacted by environmental factors, such as surrounding obstacles, which leads to UWB measurements being influenced by multipath delays. Furthermore, the authors of [24] claimed that UWB measurements can be affected by errors in signal processing and that they can be potentially eliminated by adding multiple antennas. Therefore, further filtering processes should be applied in order to have accurate measurements.…”

Lora RTT Ranging Characterization and Indoor Positioning System

“…However, the Global Positioning System (GPS) is unable to provide the indoor positioning service, which is commonly used for outdoor positioning. The research on indoor positioning technologies has been conducted for more than three decades, such as Radio Frequency Identification (RFID) [5,6], WiFi [7,8], Ultra Wide Band (UWB) [9][10][11], Pseudolite [12][13][14], Bluetooth [15], and Inertial Navigation System (INS), but they may not be suitable for Internet of Things (IoT) applications in terms of cost, application mode, and terminal power consumption.…”