The FCC has released results from its first tests of prototype Wi-Fi devices operating in the 5.9 GHz band. It found they could detect and avoid other short-range services already using the band for vehicle communications. The US regulator started a public consultation on the results, seeking feedback on how the industry sees use of the band developing.
The FCC outlined in 2016 already a test plan for evaluating the 5.9 GHz band ( 5,850-5,925 MHz) for shared use by unlicensed devices. In the first phase of tests, Cisco, Qualcomm, KEA Tech, Broadcom and CAV technologies submitted devices for testing. The prototypes were designed to prevent interference by detecting signals from Dedicated Short Range Communications (DSRC) systems operating in the band and then either vacating the spectrum entirely or sharing a portion of the spectrum with non-safety related communications using techniques similar to Wi-Fi sharing.
DSRC systems are used mainly for vehicle-to-vehicle or vehicle-to-infrastructure communications. Since the FCC first started looking at the band for Wi-Fi use, the connected car communications market has evolved further, and the regulator wants industry input on how techniques such as cellular vehicle-to-everything (V2X) and autonomous cars are expected to develop.
Comments in the consultation are due by 13 December. Two further test phases are planned for looking at unlicensed use of the band.
The 5.9 GHz band is reserved in the US for V2X, but commercial applications have yet to take off. Since it was first reserved, other services have developed for using the frequencies, including the mobile industry's plans for Cellular V2X.
