uAvionix has received approval from the FAA Spectrum Office to develop and test an ‘ADS-B like’ solution for UAS remote ID and Detect and Avoid (DAA) capability.
The solution, notionally called “UDS-B” leverages similar protocols and structures as ADS-B but operates on a different, non-interfering frequency and contains message content that is adjusted to be appropriate for unmanned systems.
Core principals of the UDS-B framework include the UDS-B leveraging FAA authorised protected spectrum meaning both FAA and FCC have to approve devices that transmit in this range, and approval can be specific to each operation.
The use of the spectrum would also allow more secure and higher power transmission for longer ranges than devices operating in the Industrial, Scientific, and Medical (ISM) frequencies such as Bluetooth or Wi-Fi.
The starting point for the message protocol is the Universal Access Transceiver (UAT) protocol of ADS-B which works well in deconflicting messages in a high traffic environment.
It is expected that ultimately, fields could be altered under industry initiative to expand the available unique addresses, include important fields like launch location or operator info, and address encryption.
Existing ADS-B radios can be “retuned” to adjust to the new frequency.
uAvionix detailed how the key to success for the L-Band application is to utilize what is known as “DME Whitespace.”
It said that at any given time at a given location and altitude, dozens of DME channels in the 960-1215MHz range are unused owing to their known geographic distribution within the NAS, relatively short transmission range, and very low transmission rates.
A section of airspace where DME frequencies are currently not in use is known as “DME Whitespace”. DME Whitespace represents available spectrum that can be used dynamically by low-altitude UAS for command and control or surveillance applications by leveraging modern digital radios that are location-aware and can change their operating frequencies prior to or during flight.