Introduction of SKYLAB UWB TWR Passive Positioning System

SKYLAB has developed and launched the Mi Bluetooth indoor positioning kit and the TDoA UWB indoor positioning kit. In response to the TWR ranging needs of some industry customers, SKYLAB has launched TWR active positioning system and TWR passive positioning system. In this article, I will introduce the TWR passive positioning system in detail.

Introduction of UWB TWR Passive Positioning System

The principle of the TWR passive positioning system is similar to that of TDoA. Real-time ranging between UWB tags and UWB base stations. It uploads the distance information to the background resetter through the UWB base station. Then the server parses the location information of the UWB tag.

Fig.1

SKYLAB UWB TWR positioning system includes UWB positioning base station, UWB positioning tag and POE switch, server, and terminal display device. Customers can build a high-precision display environment for fast and on-site high-precision UWB positioning demonstrations.

Working principle of UWB TWR indoor positioning

TWR is a two-way ranging algorithm. Algorithms transmit wireless signals to base stations based on tags. The base station sends the wireless signal to the tag after receiving the wireless signal from the tag. After the tag receives the data, it sends it to the base station again. The base station calculates the distance by the time of three flights of radio waves between the base station and the tag.

Fig.2

TWR passive positioning system product introduction（1）UWB TWR ranging base station VDU2506

●VDU2506 is a UWB positioning base station that supports TWR two-way ranging. It has a coverage radius of 400m+ and supports 1000m two-way ranging. VDU2506 supports all channels ch1-5, uses a POE power supply, and has an IP67 rating. It supports TWR/TDOA positioning algorithm, and the positioning accuracy is less than 30 cm.

Fig.3

●UWB TWR ranging module SKU620

SKU620 is a long-distance UWB ranging module. It has a positioning accuracy of 10cm-30cm and supports long-distance ranging from 500 meters. SKU620 is developed based on the DW1000 solution and supports IEEE802.15.4-2011 UWB protocol. It integrates the nRF52832 main control chip and provides multiple interfaces, which is convenient for customers to carry out secondary development.

Fig.4

●UWB TWR ranging tag VDU1506R

The uwb tag VDU1506R supports 1000m TWR two-way distance measurement and positioning. It is developed based on the DW1000 solution, with an integrated SOS button, IP66 waterproof and dustproof. VDU1506R supports two installation methods, which can be installed on the safety helmet.

Fig.5

●UWB TWR ranging tag VDU1501R

VDU1501R is a uwb positioning tag work card. It integrates DW1000 and nRF52832 and supports TDOA/TWR positioning algorithm. The positioning accuracy of VDU1501R is 10-30 cm. It is equipped with an SOS button, IP67 waterproof, and a lanyard. VDU1501R supports UWB positioning and ranging applications.

Fig.6

TWR passive positioning system product installation requirements

In order to achieve the best positioning effect, customers should pay attention to the following items when installing the base station.

●Accurate calibration requires the installation of at least 4 UWB base stations. Calibration works best in areas surrounded by base stations.

●All base stations are at least 15 cm away from ceilings and walls. There should be no shelter around the antenna of the base station.

●The installation height of the base station needs to be more than 2.5m above the ground. The distance between base stations depends on the transmit power of tags and base stations. The maximum gain of single-stage PA can reach 200 meters, and the maximum gain of two-stage PA can reach 500 meters.

●The installation location of the base station should be more than 15cm away from the ceiling and walls

Reference installation model

According to the installation requirements, you can install 4 UWB base stations at the top four corners of the positioning area. UWB tags can be positioned within a three-dimensional space area surrounded by four UWB base stations. The distance between UWB base stations can be controlled within 200 meters.

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