Bluetooth: Direction Finding Periodic Advertising Beacon
A simple application demonstrating the BLE Direction Finding CTE Broadcaster functionality by sending Constant Tone Extension with periodic advertising PDUs.
Antenna matrix for AoD (optional)
Check your SoC’s product specification for Direction Finding support if you are unsure.
Building and Running
By default the application supports Angle of Arrival (AoA) and Angle of Departure (AoD) mode.
To use Angle of Arrival mode only, build this application as follows, changing
nrf52833dk_nrf52833 as needed for your board:
west build -b nrf52833dk_nrf52833 samples/bluetooth/direction_finding_connectionless_tx -- -DEXTRA_CONF_FILE=overlay-aoa.conf west flash
To run the application on nRF5340DK, a Bluetooth controller application must also run on the network core. The samples/bluetooth/hci_rpmsg sample application may be used. To build this sample with direction finding support enabled:
Copy samples/bluetooth/direction_finding_connectionless_tx/boards/nrf52833dk_nrf52833.overlay to a new file,
Make sure the same GPIO pins are assigned to Direction Finding Extension in file samples/bluetooth/direction_finding_connectionless_tx/boards/nrf5340dk_nrf5340_cpuapp.overlay. as those in the created file
Copy samples/bluetooth/direction_finding_connectionless_tx/boards/nrf52833dk_nrf52833.conf to a new file,
samples/bluetooth/hci_rpmsg/boards/nrf5340dk_nrf5340_cpunet.conf. Add the line
CONFIG_BT_EXT_ADV=yto enable extended size of
CONFIG_BT_BUF_CMD_TX_SIZEto support the LE Set Extended Advertising Data command.
Antenna matrix configuration
To use this sample with Angle of Departure enabled on Nordic SoCs, additional
configuration must be provided via devicetree to enable
control of the antenna array, as well as via the
ant_patterns array in the
An example devicetree overlay is in
You can customize this overlay when building for the same board, or create your
own board-specific overlay in the same directory for a different board. See
nordic,nrf-radio for documentation on the properties used in
this overlay. See Set devicetree overlays for information on setting up
and using overlays.
Note that antenna matrix configuration for the nRF5340 SoC is part of the
network core application. When Bluetooth: HCI RPMsg is used as
network core application, the antenna matrix configuration should be stored in
In addition to the devicetree configuration, to successfully use the Direction
Finding locator when the AoA mode is enabled, also update the antenna patterns
ant_patterns array in