We Will Never
Get Lost Again.
In AoA, assets/tags broadcast their locations to locators, and the locators with multiple antennas measure the signal’s arrival angle and calculate the position of the assets/tags. AoA use cases include Real Time Location Systems (RTLS) for asset tracking, item finding, Point of Interest (PoI), and secure remote access control.
Angle of Arrival (AoA) technique can also be applied in UWB by using Phase Difference of Arrival (PDoA). AoA can be calculated by measuring the phase difference of received signals between two antennas.
UWB use cases can be implemented in a variety of IoT and automotive applications, including RTLS for asset tracking, secure remote access control, IPS and home automation.
Bluetooth 5 Low Energy
Bluetooth has two major Direction Finding techniques- RSSI (Received Signal Strength Indication) and Angle of Arrival (AoA)/Angle of Departure (AoD).
AoA/AoD were introduced in Bluetooth 5.1 to improve its location service capabilities. RSSI provides distance estimation based on signal strength, whereas AoA/AoD provides angles of the tracked device or the locators to calculate the directions. Working together, the two techniques can determine device location with sub-meter accuracy.
In AoD, locators broadcast their location information using multiple antennas, and the smart phones/wearables calculate the received signals’ departure angles and calculate the position of itself. AoD use cases include Indoor Positioning Systems (IPS) for way finding, item finding, Point of Interest (PoI), and secure remote access control.
IEEE 802.15.4z impulse radio UWB is a secure ranging technology providing centimeter level location measurement accuracy.
UWB has two major ranging techniques- Time of Flight (ToF) and Time Difference of Arrival (TDoA).
UWB uses Time of Flight (ToF) in Two Way Ranging. ToF of the UWB signal traveled from the device to locator and back is measured to calculate the distance. Whereas Time Difference of Arrival (TDoA) measures the time difference of the UWB signals received by nearby locators to calculate the location of the device.
BLE + UWB
The ubiquity and interoperability make Bluetooth the most widely used wireless technology in mobile and IoT applications. But BLE isn’t as precise as UWB in fine ranging and localization but can operate at very low power. BLE uses RSSI + AoA/AoD can determine location with sub-meter accuracy, whereas UWB uses ToF + AoA can pinpoint location to within +/-10cm.
A wide range of use cases can benefit from the combination of BLE and UWB. Consumer tags, smart home devices, automotive access, mobile devices, access control and digital keys.
BLE + UWB together enable better location accuracy for battery-operated systems. In spatial awareness applications, BLE can perform low power discovery of other devices, initialization and authentication, then activate UWB to perform precise distance measurement. UWB is woken up only when it’s required, therefore allowing devices to have extended battery life.