Mode DJI drones

DJI drones: OcuSync / Lightbridge-like signals by shape, and DroneID packets decoded.

Group	Aviation
Default frequency	2440 MHz
Default sample rate	20 Msps
In the mode list	Drones, 2.4 / 5.8 GHz

Step-by-step: Tutorial-DJI-drones

What DJI drones is

DJI drone links use wideband OFDM on 2.4 and 5.8 GHz. OnAir classifies the bursts by shape and can read the DroneID broadcast of supported models; this is a guess from the signal, never a certain identification.

Frequencies and settings

Setting	Value
Start frequency	2440 MHz
Tuning range of the mode table	2300 to 6000 MHz
Sample rate asked	20 Msps
Lowest working rate	16 Msps
Channel width	20 MHz

OnAir takes any frequency you type; the numbers above are the mode's starting point and the range its table describes. In the app the shortcut label is Drones, 2.4 / 5.8 GHz.

What OnAir shows

DJI drones on 2.4 and 5.8 GHz, receive only: wideband OFDM burst trains are classified by their shape (OcuSync-like, Lightbridge-like, unknown wideband OFDM) from the width, burst period, duty cycle and cyclic-prefix correlation, with a confidence and a clear note that this is a guess from the signal shape; DJI DroneID (the OcuSync 2 broadcast: Zadoff-Chu roots 600 and 147, turbo code, CRC-24) is decoded to the drone's serial number, position, home point and pilot position as sent in the clear. Needs 16 Msps or more (HackRF at 20 Msps; Pluto, bladeRF, USRP). The encrypted video link is never decoded.

The mode's own tab has these screens: Signals, DroneID, Bursts. The other tabs (Overview, Receiver, Scan, History) are described on the Main window page.

Tips and caveats

• Checked with generated signals and impairments; recordings of real signals welcome.
• Which radio: No: this mode needs a radio that samples at 16 Msps or more, and an RTL-SDR reaches about 2.4 Msps.
• Try it without a radio: most modes include a built-in synthetic test signal, so you can open the screen and try the controls first.
• Receiving and the law: Receiving aircraft broadcasts is legal in many countries, but some restrict listening to or using what you hear. OnAir is a receiver. Check the rules where you live. See Legal.

Related pages

• All modes, Aviation
• Supported radios, Troubleshooting, FAQ
• More in Aviation: ADS-B, Mode S uplink, ACARS, VDL2, VDL4, HFDL, Airband, VOR, ILS, NDB, Drone Remote ID, UAT, FLARM