Angle of Arrival – High-precision positioning with the AoA method

For use cases that require extremely precise positioning, Favendo uses the AoA method for positioning. AoA stands for Angle of Arrival. With this method, in addition to the signal strength (RSSI method), the time difference of (the signal) arrival (TDOA) is also included in the calculation and converted into extremely precise positioning. In this way, sub-meter positioning accuracies between 0.1-1 m can be achieved with Bluetooth technology. Favendo is an official partner of Quuppa and uses Quuppa Locators, which are equipped with special antennas for these applications.

The set-up costs for the infrastructure are slightly higher when using Quuppa Locators instead of Favendo’s Relay-Beacon Tracker due to the more complex planning and installation procedure, but still remain far below the costs of a UWB system.

Combined Positioning Software

A combination of both methods is possible, so for areas where centimeter-precise positioning is not necessary, the less expensive hardware can be used. In areas where this very precise localization is necessary, locators are used.

RSSI vs. AoA

Both terms denote methods for calculating a position based on Bluetooth technology. In the case of positioning based on the Received Signal Strength Indicator (RSSI), the Beacon Tracker measures the strength of the signal that the asset tags – the transmitters with which the assets to be tracked are equipped – permanently transmit. A simple picture to understand is the waves that a stone thrown into the water “emits” and which weaken with increasing distance. This type of position determination by means of distance measurement based on signal strengths is called lateration, the effect of decreasing signal strength, which is used here, is called attenuation.

A position calculation based on the Angle of Arrival (AoA) is also called triangulation. In contrast to lateration, triangulation uses not only the distance to the signal generator but also angles to determine the position of an object. For a two-dimensional position determination two angles and one length are required. Angle – technically “Angle of arrival” (AoA) – refers to the angle at which the signal meets the receiver.

The angle is measured using the delay of the signal (“Time of Flight” TOF). TOF measures the time it takes a signal to travel between an object and a reference point. This position calculation is very accurate. However, the effort to set up the necessary infrastructure for the receiver is greater than with an infrastructure designed for RSSI. The method is currently not suitable for mobile indoor navigation.

Use cases for Angle of Arrival Positioning

High-precision asset tracking is at home in Industry 4.0, logistics and healthcare. It enables the fast and reliable location of tools, medical devices and production equipment as well as small parts. At the same time, AoA-Tracking also allows the secure identification of closely positioned assets, so that large parts can be tracked reliably and precisely in narrow environments.

  • Centimeter accurate tracking
  • Tracking assets of any size that are close together

Asset Tracking in production halls

For example, an aircraft engine manufacturer wants to identify and track the position of its unfinished engines in its manufacturing hall. Although the engines are very large, they cannot be tracked reliably using an RSSI-based method because the positioning is too inaccurate to identify the large objects stored next to each other. AoA Positioning is sufficiently accurate to be able to distinguish the objects even in confined spaces and reliably identify the required workpiece.

Asset Tracking in hospitals

In a hospital, thousands of pieces of equipment must be reliably available and easy to find. Especially in those cases where time pressure plays a major role, it is important not only to get an approximate position like a certain storage location, but also to have exact information about where the item you are looking for is actually located.

High-precision people tracking

For staff working alone, high-precision tracking is a special safety factor, especially in critical situations in complex environments. For example, when a single worker has an accident in a petrochemical plant. In emergencies, help can be sent directly to the person and not just to the respective section. The Wearable is still an extremely reliable and basic Bluetooth transmitter.


Meet Favendo

Favendo is the trusted partner for superior Real Time Location Services. Our Team is committed to providing timely and cost effective solutions for cruise industry, large shopping malls, public venues, industrial surroundings and more. To offer our customers the most suitable system we partner with Quuppa and Abeeway. Come and meet Favendo.