WINKEL

The ability to determine the location of objects at any time (real-time localization) is a key technology of the Internet of Things (IoT) and the digital transformation. Outside of buildings, satellite-based navigation systems, such as GPS, are well established. However, such systems cannot be used within buildings, so alternative approaches must be considered.

The aim of WINKEL is the development of an innovative infrastructure-less localization system based on ultra-wideband (UWB) technology, which can be integrated into existing environments with little effort and is able to locate a large number of mobile objects in real time. The project’s main innovation is the combination of highly accurate angle of arrival (AoA) measurements and extremely fast and highly accurate distance measurements based on UWB signals in order to determine the unknown position of mobile objects.

The distance between UWB transceivers can be obtained by performing time of flight measurements. Additionally an AoA estimate can be generated by precisely capturing the signal's arrival time at multiple UWB transceivers. Therefore, novel radio nodes, so-called AoA anchors, will be developed during the project. These special nodes will provide both, distance and angle information relative to other communication partners.

AoA anchors know their own position in space and can therefore serve as reference or infrastructure units. They can either be installed in a fixed position or be mounted on mobile platforms, such as automated guided vehicles (AGV) or forklift trucks. Functioning as mobile infrastructure nodes, AoA anchors can thus increase the coverage of an area with reference information and reduce the required amount of fixed anchors.

In order to localize mobile objects, they are equipped with an UWB transceiver (tag) or a mobile AoA anchor. The localization of an object is possible given only the relative angle and the distance to a single AoA anchor. Compared to other approaches, this means, that the required number of infrastructure nodes is small. By reducing the time required to perform a distance measurement, a large number of objects can be located with high accuracy in real time.

Furthermore, in autonomous navigation of vehicles, orientation awareness is of immense importance in addition to knowing the vehicle's position. By equipping a vehicle with a single AoA anchor, it is possible to obtain its orientation directly. Finally, relative localization of other vehicles or humans for the purpose of collision avoidance can also be realized using a single AoA anchor per vehicle.

In addition to performing measurements, all radio nodes can communicate with each other and thus exchange local information. Once the position of a mobile object has been estimated, it can be sent to other nodes 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 will therefore be used in the project.