The NAB is calling more attention to DSRC, a new radio service being developed under the federal government’s Intelligent Transportation System program. The Dedicated Short Range Communications service “promises to accomplish in a far superior fashion the goals touted by recent FCC filings for new safety-related services in the broadcasting bands,” the NAB states in its latest TechCheck newsletter to members.
The NAB prefers this approach to systems that would air emergency vehicle warnings to nearby motorists over the AM/FM bands.
The FCC has adopted service rules under which DSRC would operate based on a standard called ASTM-DSRC, and apply to 75 MHz of spectrum in the 5.9 GHz band allocated for the service. DSRC involves vehicle-to-vehicle and vehicle-to-roadside communications that could warn drivers of an impending dangerous condition or event.
“For example,” the NAB writes, “one application made possible by DSRC is intersection collision avoidance (e.g., audible alarm like “Intersection ahead with red light – STOP”). This would use roadside speed and location sensing equipment, DSRC equipment, in-vehicle signing and trajectory computing and control electronics to help drivers avoid intersection collisions, the most prevalent type of traffic accident in the U.S.
“The commission notes in their Report and Order that since ‘…802.11a equipment is readily available, adopting the ASTM-DSRC Standard will promote the rapid development and deployment of DSRC equipment,'” NAB stated.
This standard specifies Orthogonal Frequency Division Multiplexing as the means of transmission, states NAB. OFDM is also the modulation technique used by Ibiquity Digital Corp. for its AM and FM IBOC digital radio services.
NAB also argues that DSRC allows directionalized alerts, which contrasts with the broadcast band services that are being proposed. Those use omnidirectional antennas “and offer no clue to the listener regarding the direction in which the emergency vehicle is traveling” states the trade association.
NAB Likes Dedicated Short Range Communications
NAB Likes Dedicated Short Range Communications
