Angle-Based Cooperative Real-Time Localization in Low-Infrastructure Environments
The ability to determine the position of objects at any given moment (real-time localization) is a key technology of the Internet of Things (IoT) and digital transformation. Outside of buildings, satellite-based navigation systems, such as GPS, are well established. Inside buildings, however, such systems cannot be used, so alternative approaches must be employed.
The goal of WINKEL is to develop a novel, low-infrastructure localization system based on Ultra-Wideband (UWB) radio technology that can be easily integrated into existing environments and enables the real-time tracking of a large number of mobile objects. At the heart of this innovation is the combination of highly accurate arrival angle measurements and extremely fast, equally highly accurate distance measurements based on UWB signals to determine the unknown position of mobile objects.
The distance between UWB transceivers can be determined by measuring the signal propagation time. By precisely detecting the signal arrival at the antennas of multiple UWB transceivers, it is also possible to estimate the angle of arrival (AoA). As part of the project, special, novel radio nodes—so-called AoA anchors—are therefore being developed that can provide not only distance information but also relative angular information regarding other communication partners.
AoA anchors know their own position in space and therefore serve as reference or infrastructure units. They can be installed in fixed locations or, alternatively, on mobile platforms, such as automated guided vehicles (AGVs) or forklifts. As mobile infrastructure nodes, AoA anchors can thus increase the coverage of an environment with reference data and also reduce the number of fixed anchors required.
To locate mobile objects, they are equipped with a UWB transceiver (tag) or a mobile AoA anchor. It is then possible to locate an object simply by knowing its relative angle and distance to a single AoA anchor. Unlike other approaches, this keeps the number of required infrastructure nodes low. By reducing the time required per distance measurement, a large number of objects can also be located with high accuracy in real time.
Furthermore, in the context of autonomous vehicle navigation, orientation information is of immense importance in addition to knowing the vehicle’s own position. A single AoA anchor per vehicle can provide this information directly. Finally, the relative positioning of other vehicles or people for the purpose of collision avoidance can also be achieved using a single AoA anchor installed on the vehicle.
In addition to collecting measurement data, all radio nodes can communicate with one another and thus exchange payload data. Once the position of a mobile object has been estimated, this information can be made available to other participants and thus serve as additional reference information. This method, known as “cooperative localization,” can further increase the coverage and accuracy of the overall system and is therefore being used in the project.
Project Partner
Funding
Funding Code
ZF4642201ED8