UWB DEBATE GOES INTERNATIONAL AT FIRST ITU STUDY GROUP MEETING

“This is just putting the initial cards on the table,” said one source, who noted that many of submissions for meeting came in at 11th hour: “It’s going to take people time to go back home and digest them.” Joint filing by Ericsson, Nortel and Qualcomm showed that some of same interference assessment material submitted in U.S. as part of FCC policy formation last year was being resubmitted in international arena, source said: “The question is, will you get the same answer?”

Meanwhile, in U.S., FCC is expected to rule next month on petitions for reconsideration of Feb. 2002 UWB order. Last year, agency had said it would be revisiting what it described as “conservative” rules for UWB within 12 months to ascertain whether changes were needed. Lack of real-world UWB devices that are commercially available to test has meant that isn’t likely to happen within original deadline, Office of Engineering & Technology Chief Edmond Thomas said. Last fall, FCC staff report said ambient noise levels in certain environments were far greater than interference threshold used as basis for UWB limits at some test sites.

“We see no reason, based on the measurements so far, to change the rules,” Thomas told us after last week’s FCC meeting. “The reason we don’t want to make the rules more lax is because we haven’t really tested any ultra-wideband devices because the order was in February and they're just coming online now.” In coming year, FCC plans to test lots of ultra-wideband devices and “check their interaction with incumbent services,” he said. “Then, based on that, if there’s a reason to make additional changes, we will.”

Several European submissions to ITU’s Study Group 1/8 provide first glimpse of what those administrations are examining in relatively nascent area of UWB regulation beyond U.S. France, Germany, Switzerland and others refer to both spectrum masks in in FCC order and modified proposal developed by European Conference of Postal & Telecommunications Administrations (CEPT) in July. Expert said that among challenges in 4-day meeting was extent to which different administrations would measure interference potential against systems different from those used in U.S. For example, Switzerland discussed protection distances for UWB interference in systems such as Bluetooth and DVB-T, which is European DTV standard. Several sources have described Study Group meeting as starting point for discussion of policy issues, including potential interference to incumbent systems, beginning on international level.

France raised concerns that passive services applications, which are used in Earth Exploration Satellite Service (EESS) band, be protected. Those systems are used for weather forecasts and climate monitoring. Concerns were raised in fall by federal agencies, including NOAA, over development of U.S. policy contributions to ITU. Some U.S. agencies argued that policy shouldn’t allow national administrations to authorize vehicular radar on unlicensed, noninterfering basis at 23.6-24 GHz. Those systems use UWB- based radar systems to provide safety services such as crash detection. ITU Radio Regulations 4.4 stipulates that administrations have sovereign right to use spectrum in manner they choose without causing harmful interference to others operating under those rules. Concern of NOAA and others had been that Article 15 of Radio Regulations barred emissions in certain bands, including 23.6-27 GHz, where car- based UWB radar systems operate. Short Range Automotive Radar Frequency Allocation (SARA) industry group contended U.S. had ability under sovereignty language of No. 4.4 to allow such operations, even in light of restrictions of Article 15. It also said FCC already provided for such uses.

Some of debate involved footnote to Article 15 intended to protect passive services. Issue was whether footnote, meant to keep those bands free of potential sources of harmful interference, barred administrations from allowing nonconforming uses.

France recommended UWB devices be designed to avoid exclusive frequency bands, such as passive applications, covered by that footnote. As example, it said UWB designs could use notch filter at exclusive frequency band so power output “would be reduced to an extremely low level.” As part of its proposed guidelines, it said UWB devices “cannot be considered as spurious emissions due to continuous frequency coverage over the whole band used.” Spurious emissions typically are sporadic “and do not cover the whole adjacent spectrum,” proposal said. France said if UWB designs couldn’t be structured to avoid passive spectrum, compatibility studies should be undertaken between passive sensors and UWB devices.

Multinational German company Robert Bosch said European auto industry planned to implement short-range UWB radar at 24 GHz. It said European Commission had released eSafety Action Plan that identified short-range radar at 24 GHz as part of planned road safety changes in Europe. CEPT’s Electronic Communications Committee also is studying how to implement applications at 24 GHz on interim basis to avoid interference to incumbents. Barring operation of technology in passive services spectrum would contradict sovereignty protections of ITU Constitution, Bosch said. It said “accepted international practice” allows nonconforming operations in such bands on noninterference basis if there are other national policy issues at stake. Prohibiting such operations would be contrary to national practice “and spectrum management if it would thereby preclude active safety devices that will be a critical component for enhancement of road safety,” Bosch said. “Such a conclusion also would constrain future policy discussions by administrations with respect to other new UWB technologies, which by their nature occupy large bands of spectrum but with proper conditions could operate in such a manner that avoids harmful interference.”

Canada proposed method to calculate compatibility between mobile wireless systems and in-band emissions from UWB technology. It suggested power output of UWB devices be less than -73 dBm/MHz to provide protection distance of 1 m for wireless receivers. Canada said wireless phone users expected handsets to provide service everywhere, even in buildings where signal strength might be at a minimum and handset receiver was at maximum sensitivity. Such environments could contain UWB wireless local area networks that wouldn’t be obvious to wireless subscribers who experienced interference, Canada said: “Users of the mobile service currently are accustomed to successfully operating their handset receivers at distances of a meter or less from common machinery, electrical and electronic equipment. If the UWB devices become ubiquitous for communications in indoor environments, then the mobile system users will expect to receive service when in similar proximity to the UWB devices and systems.” Filing said UWB systems were expected to involve multiple nodes communicating with one another, meaning “there will likely be several interferers in the region near the mobile system receiver.” Protection distance of 1 m wouldn’t guarantee “protection for all users’ expectations and a shorter protection distance (and consequently lower emission limit) may be needed for certain UWB deployments,” Canada said.

Ericsson, Nortel and Qualcomm filing included results of study they conducted on compatibility between UWB and PCS and GPS systems. Earlier versions had been submitted to FCC before Feb. 14 order and companies said they had updated them to reflect those rules. Filing said lab tests showed that close proximity of UWB devices to PCS phone operating at 1850-1910 MHz/1930-1990 MHz would degrade phone’s equivalent noise figure to extent of “rendering its operation useless, especially in marginal coverage areas.” Studies also showed that UWB emissions in GPS band raised noise floor of GPS sensor to point that it would prevent GPS-enabled wireless handset unable to pinpoint location of 911 caller. Companies asked that: (1) Study results be included in study group’s working documents on definitions and characteristics of UWB. (2) ITU study aggregate effect of multiple UWB devices on various services. They said study examined impact of single UWB device on PCS and GPS receivers. “However it is likely that the aggregation of many UWB devices will further degrade the performance of PCS and GPS receivers,” it said.