AVIATION OFFICIALS RAISE NEW ROUND OF UWB INTERFERENCE CONCERNS

Aviation interests, including FAA officials, and GPS industry have raised some of loudest concerns in past about potential of UWB technology to interfere. Airline officials and federal regulators told WAEA that their latest worries on technology centered on formation of international policy at ITU, current federal test efforts and potential loosening of some of FCC’s emissions limits next year. Noting that FCC had indicated it would reexamine rules within one year of approval of Feb. 2002 order, Frodge said: “It’s quite clear that change is imminent.” Other concerns raised by aviation community at conference centered on what they charged was lack of transparency of FCC test methodology for UWB devices and how airlines in future could enforce rules that would bar passengers from taking devices aboard aircraft that were UWB- equipped.

Task Group 1/8 in U.S. has been focusing on U.S. input into ITU policy for UWB, creating possibility that policy could be up for consideration at World Radio Conference in 2003, Frodge said. One possible place that UWB-related policy could emerge involves agenda item for harmonizing spectrum for public safety uses internationally, she said. “Very soon we will have rippling effects internationally,” she said. Key concern for DoT on outcome of UWB regulations domestically and internationally is that 80% of currently operational air traffic control systems in U.S. are in 960 MHz and below, she said. Frodge told reporters after panel discussion that that was conservative figure and more accurate estimate would be closer to 90%. U.S. transportation systems in that band include high-frequency communications, VHF air/ground communications, instrument landing system glidescope and marker beacons, she said. In addition, GPS L5 for civilian systems will launch this decade in that spectrum, she said: “Ultrawideband has the potential to touch on a lot of these systems.”

Among concerns that Frodge raised about FCC policy was that Commission in 1999 authorized waiver for 3 manufacturers to move forward with UWB under special temporary authorities. She said that could have provided opportunity to provide prototypes for data to base decisions on rule. “We saw no data come from this,” she said. Frodge said June House hearing included testimony from officials who called for real-world testing on prototypes. “We have yet to see real- world data on this,” she said. In July, FCC issued waiver for legacy ground-penetrating radar systems to file with agency, she said. “These are unknown numbers of systems and unknown power limits and unknown operational frequency ranges,” Frodge said. She also said FCC recently released staff report on UWB testing that examined ambient radiofrequency noise levels in GPS and other bands. FCC lab measured emissions from devices ranging from PCs to electric drills, finding they had emissions above limits set for UWB devices in Feb. order but still within Part 15 limits. “There is a lot of information in there but not a lot of it is focused on UWB,” Frodge said: “It would be very beneficial to combine this with some actual prototype UWB devices.”

FAA told us last week that testing had begun on prototype UWB system and ground-penetrating radar unit at its technical center in Atlantic City (CD Nov 18 p5). Frodge said funding constraints that continuing resolution created didn’t appear to have any impact on advancing of testing. She told reporters after panel discussion that tight financial situation could have effect on resources needed to analyze data and allow it to be input into current regulatory process. United Airlines’ Miller said that one concern that prompted testing was interference incident last year at JFK International Airport in N.Y. in which ground-penetrating radar unit appeared to cause interference with air traffic control system. Frodge declined to elaborate on follow-up report on incident, saying assessment wasn’t finalized on possible linkage between GPR operation and interference incident. She said event was involved when GPR was operating in demonstration and air traffic control system experienced interference. Frodge said GPR was shut down and interference stopped. GPR has applications for FAA facilities such as providing images of underground cable. Tests haven’t yet been finalized at FAA that determine link between device and interference incident, she said, declining to speculate on connection between GPR demo and incident.

Separately, several FAA officials said they expected RTCA, formerly Radio & Technical Commission for Aeronautics, would move ahead with special committee to examine potential impact of personal electronic device use on aircraft (CD Nov 20 p2). Intel Labs Co-Dir. of Wireless Research Jeffrey Schiffer said conference marked first time FAA had committed publicly to moving ahead with request to RTCA to set up new advisory panel. “There’s developing policy going on right now,” said Charles Fellows, chief scientist of FAA Flight Standards. “We're not only struggling with the portable electronic device/wireless connectivity connected with the entertainment industry. We are also dealing right now in our own spectrum with the use of devices by the flight crew on board the aircraft concurrently with this study.” Several officials said in panel discussions that although concerns had been raised about UWB device use on aircraft, FCC policy specifically restricted use of technology on airplanes.

United Airlines’ James Miller said while aviation industry wanted to use new wireless technology, it remained concerned on potential impact to safety-of-life systems. “The rush to profit should not override safety mechanisms now in place,” he said. Miller called for balance between regulatory policies that made way for new technologies such as UWB while at same time protecting such as GPS and instrument-landing systems. “The airlines, of course, are stuck in the middle of this tug of war,” he said. As example of extent to which United is using new wireless systems, he said airline installed in-cabin surveillance system on 747 this year. “We are working to develop an electronic flight bag for all of our pilots,” he said.

Concern of United and others in industry is pace at which rules were put in place -- and could be changed -- before test data that evaluated interference on real systems was assessed. New, spectrum-intensive communications architecture for next-generation aviation systems “is being destroyed even as we work to construct it,” Miller said. “Aviation spectrum is prime, beachfront property. It is desired by some because it is global.” One critical concern is that programs such as direct routing between transoceanic cities could be compromised if FAA didn’t have spectrum protection.

“We have all taken this position that the government will protect us,” Miller said. “Unfortunately, times have changed and airlines have to defend why the spectrum is important to them. There is a growing ‘kick them while they are down’ mentality. Organizations like the FCC know we are distracted. We are trying to survive. Now is the time to try to take those frequencies away from us.”

Among concerns raised at WAEA conference was potential aggregate effect of UWB devices and their potential to affect avionics systems if brought aboard aircraft in laptop PCs. Answering question about proposed rollout of UWB technology in broad range of consumer devices, Julius Knapp, deputy chief of FCC’s Office of Engineering & Technology, said aggregation issue was examined closely when Commission crafted UWB rules. Sheer number of devices deployed isn’t as important as actual number of devices operating in particular area, he said, saying UWB device operating in Baltimore couldn’t contribute to aggregation effect for devices running in Washington. “There is some additive effect,” he said. FCC addressed that possibility in UWB emissions limits that contain margins that take that factor into account, he said. As example, he said standard for UWB technology for GPS bands was 40 dB below existing limit in Part 15 rules for device such as laptops. While several conference participants raised concerns about current lack of real-world test data, FCC has said that staff report examined noise floors because there were not yet commercially available UWB devices available for testing. Commission has said it will test those units when they are rolled out in marketplace.