CARROLL MCCORMICK / MONTREAL
The US Federal Communications Commission (FCC) has failed in its responsibility to provide a reasoned basis for its actions, to make rational connections between the facts and its decision, or to make decisions consistent with its Part 15 rules governing radio frequency devices, according to a US group.
The allegations are made in a draft petition for reconsideration prepared for the Aviation Telecommunications Coalition (ATC), formed to fight the unlicensed use of ultra-wideband (UWB) devices.
The final version of this critique of the FCC's First Report and Order (R&O), which approves the use of certain classes of UWB devices, is expected to go to the FCC by 17 June. In February, the FCC authorised the use of UWB devices above 3.1GHz and imposed technical limits below 3.1GHZ, despite opposition from airlines and general aviation operators (Flight International, 26 February-4 March).
Devices using UWB technology will broadcast weak signals over vast swathes of the aeronautical spectrum. Opponents fear this will interfere with their licensed systems and render unsafe aeronautical systems such as those using the global positioning system.
The draft argues that the R&O did not establish limits that will prevent interference. It adds that the FCC conclusion that interference can be mitigated by the users of authorised systems is contrary to the Part 15 requirement that interfering operators immediately stop their interfering.
The draft disputes the FCC accusation that UWB opponents presented overly conservative and worst-case conditions where interference could occur - for example, between UWB and digital audio radio services equipment. A conservative stance is fully justified and is the only one that can protect authorised systems, says the draft.
"Nothing in the record or common sense supports an assumption that UWB devices will be kept away from the receivers they are more likely to interfere with," it adds.
The R&O encompasses a wide variety of devices without regard to their particular interference characteristics, according to the draft. Moreover, it argues, the FCC has failed to define successfully terms that will prevent the proliferation of outdoor UWB communications infrastructure, a key UWB containment issue.
The draft says that several R&O technical findings and decisions are wrong. For example, the R&O reasons that because Part 15 devices are already operating in the 2,400-2,450MHz band, UWB devices are likely to have no significant impact.
The draft claims consistent evidence exists that UWB devices impose an interference threat. Finally, it argues that the six to 12-month FCC timetable for reviewing the limits set out in the R&O is not based on any facts, concluding that the only reason for this timetable is to allow the FCC to promote the deployment of UWB devices.
Source: Flight International
