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First IEC International Standard on EMC Measurement UncertaintyAfter seven years in development, an international standard has been published that addresses electromagnetic compatibility (EMC) measurement uncertainty. The new standard describes how to apply EMC measurement uncertainty by comparing test results to a limit to determine compliance. CISPR 16-4, "Specification for Radio Disturbance and Immunity Measuring Apparatus and Methods—Part 4: Uncertainty in EMC Measurements," was developed by the International Special Committee on Radio Interference (CISPR) Subcommittee A, which focuses on radio interference measurements and statistical methods. The publication is designed to provide guidance for EMC laboratories that need to capture and calculate their EMC test instrumentation uncertainty when being assessed to meet the requirements of ISO/IEC 17025 (2000-01), "General Requirements for the Competence of Testing and Calibration and Testing Laboratories." "This publication is the product of years of effort by CISPR in coming to grips with EMC measurement-uncertainty application and its impact on stating pass/fail for products where the test results include measurement uncertainty," says Peter J. Kerry, CISPR chairman. "This is the first of several projects in CISPR on the topic to include other facets of measurement uncertainty beyond that of the test instrumentation only, such as the test setup uncertainties presently in product compliance standards." The document describes CISPR's approach on how to use the uncertainty values indicated when determining whether products pass or fail (after accounting for measurement uncertainty). In addition, an annex to the document outlines the determination of measurement uncertainty estimates for various measurements. Kerry notes that there are other tests beyond that of radiated and conducted disturbance and power measurements (included in CISPR 16-4) that CISPR plans to add to this work program to meet the needs of the EMC community. "CISPR 16-4 is a must for every test laboratory and those who apply its principles to EMC measurements and conformity assessment," he says. The publication is primarily intended for EMC test laboratories, product committees that require the application of measurement uncertainty, lab quality assessors using ISO/IEC 17025, product manufacturers assessing the test results (including the application of EMC uncertainty) of EMC test laboratories, national metrology institutes, and those who provide education and training on the measurement uncertainty. FCC Promotes Commercial Use of Government BandsThe Federal Communications Commission (FCC) is examining possible commercial development and growth in several undeveloped government-use frequency bands. Potential uses of this spectrum would include high-speed wireless local-area networks, broadband access systems for the Internet, point-to-point communications, and point-to-multipoint communications. The bands, which include 71–76, 81–86, and 92–95 GHz, have never before been occupied by nongovernment users. FCC is seeking comment on its proposed rules to allow use of these bands for a broad range of new fixed wireless services. These new uses could be possible because of the shorter wavelengths (about 3–5 mm) and because of other technical characteristics that differentiate these bands from others. "As technology advances and the pressure to find more spectrum increases, commercial and government research efforts increasingly focus on spectrum in upper bands. There was certainly a time when commercial RF interests looked askance at spectrum at 40 GHz, let alone the 70, 80, and 90 GHz bands we examine today," says FCC commissioner Kathleen Q. Abernathy. According to FCC, this region of the spectrum is essentially undeveloped and available for new uses. FCC wants to develop a flexible and streamlined regulatory framework that will encourage innovative uses of the spectrum and accommodate future developments in technology and equipment. FCC says it seeks to promote competition in the communications services, equipment, and related markets, as well as advance the potential sharing between the federal government and other systems. FCC anticipates that its proposals will encourage the use of technologies developed in military and scientific applications to be used in a broad range of new products and services, such as high-speed wireless local-area networks and broadband access systems for the Internet. In July 2000, FCC held a public forum on possible new uses of the 92–95 GHz band. Several speakers indicated that recent technological developments would make new uses of this band practical. In July 2001, Loea Communications (Lihue, HI) experimented with technology it developed for use in the 71–76 and 81–86 GHz bands. As a result, Loea filed a petition requesting the establishment of service rules for the licensed use of those two bands. "Innovation, technological change, and increasing encumbrances in the lower bands have driven the regulatory process to open these new bands to commercial operations. This decision is the positive outgrowth of the spectrum drought in the lower bands. As currently conceived, the 70, 80, and 90 GHz bands will use pencil beams of radio energy to transmit data relatively short distances between fixed sites," Abernathy says. "In many cases, there could be thousands of these hops in a relatively small geographic area, but because of the narrow beam, it is believed multiple systems can coexist without interference. This deployment model is unlike anything we have ever seen and may require new thinking on the appropriate licensing approach," she says.
FCC Spectrum Policy Task Force
FCC has formed a task force to identify and evaluate changes in spectrum policy. The task force is charged with identifying changes that will "increase the public benefits derived from the use of radio spectrum." "The government has an almost impossible task trying to keep pace with the ever-increasing demand for spectrum and continuing advances in wireless technology and applications. In this fast-moving world, the commission cannot rely on outmoded procedures and policies," says FCC chairman Michael K. Powell. "We must establish new ways to support innovation and the efficient, flexible use of spectrum. While the spectrum policy task force has a difficult task ahead of it, I am pleased that it is making significant progress and that it is moving forward with a work plan," Powell says. Paul Kolodzy, senior spectrum policy adviser for FCC's Office of Engineering and Technology (OET), will head the cross-bureau, multidisciplinary task force. The task force will be composed of senior staff from several FCC bureaus and offices, including attorneys, engineers, and economists. The deputy director of the task force is Lauren M. Van Wazer, special counsel to the chief, OET. Dr. Michael Marcus, associate chief for technology, OET, will serve as senior technical adviser, and Maureen C. McLaughlin, senior counsel, Office of General Counsel, will serve as special counsel to the task force. The task force will receive guidance from a steering committee composed of the bureau and office chiefs to whom its members report. For additional information on the task force, go to http://www.fcc.gov/sptf.
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