UBX-21004616 - R02
Contents
Page 8 of 28
C1 - Public
2.1.2
Angle of Departure (AoD)
In AoD systems, the transmitter has multiple antennas. The receiver calculates the phase difference
between these antennas to determine the direction to the transmitter. By using this data in
combination with angle data from other transmitters, the receiver can estimate its position. An
overview of a system using this method of direction finding is shown in in Figure 4.
Figure 4: Angle of Departure (AoD) system architecture
2.1.3
Angles of measurement
In both AoA and AoD systems, the reported angles of the azimuth and elevation measurements are
compared against a reference plane, as shown in Figure 5.
Figure 5: Azimuth and elevation angles
For further information about Bluetooth direction finding, see the u-
blox webinar “
Bluetooth for High
Precision Indoor Positioning
”
available on the u-blox webinar page [8] and Bluetooth SIG technical
overview [1].
