FCC to consider 76-81 GHz band at next meeting

Bosch auto (Bosch)
Bosch has argued that the 76-81 GHz proceeding has been pending before the FCC for an inordinately and unjustifiably long time; short-range radar systems are critical to improved road safety. (Bosch)

While U.S. regulators continue to hear arguments for and against the mandate of Dedicated Short Range Communications (DSRC), the FCC will be taking up a decidedly less heated but somewhat related matter when it conducts its next open meeting on July 13.

On the agenda is a Report and Order that would address use of the 76-81 GHz band to support a broad range of vehicular radar uses, such as collision avoidance and adaptive cruise control systems, as well as to expand the types of fixed and mobile radar operations permitted within airport environments.

The 76-81 GHz band falls into the category of millimeter wave spectrum, where radio propagation decreases more rapidly with distance than at lower frequencies, but its limited range also allows for frequency reuse within very short distances, enabling a higher concentration of transmitters in an area than is possible at lower frequencies.

The Alliance of Automobile Manufacturers has a beef with a few specifics in the order, saying it’s concerned about one narrow aspect (PDF) of the draft Report and Order’s phase-out schedule for unlicensed wideband and ultra-wideband (UWB) vehicular radar operations in the 24 GHz band, as it pertains to defective or malfunctioning equipment.

But for the most part, commenters are urging the FCC to act quickly on the issue. General Motors (GM) representatives met with Chairman Ajit Pai and his staff back in April, saying adoption of the service rules spelled out in the order will allow for the deployment of vehicular short range radar within the 76-81 GHz band. GM is working with suppliers to test and optimize Short Range Vehicular Radars for developing self-driving vehicles. The radar systems are used for advanced safety features like forward-looking object detection and avoidance, collision warning, lane change assistance, blind spot detection and pedestrian protection.

The FCC’s action was in response in part to a petition for rulemaking filed by engineering company Robert Bosch LLC in 2012. In a May 5 letter (PDF) to Chairman Pai, Bosch Regional President Scott Winchip explained that the proceeding has been pending before the commission for a total of 6 years, a delay has been detrimental to the worldwide harmonization effort for automotive radars.

The two frequency ranges now in use for long-range automotive radar systems in the U.S. at 24 GHz and 76-77 GHz can’t accommodate the implementation of new safety functions for automotive radars, he said, noting that short-range vehicular radar systems in the 77-81 GHz band will assist in reducing collisions between automobiles and between automobiles and bicyclists, motorcyclists and pedestrians.

Automotive radars in Japan and Europe now use the 77-81 GHz band, and harmonization with the 77-81 GHz band would further enable cost efficiencies to also be realized in the U.S. and assist in increasing the deployment of collision mitigation systems and safety features, he added.