Clinton Raises the Bar on Spectrum Management

William Kennard

President Clinton recently announced that the federal government would be working with the Federal Communications Commission (FCC) to identify and make available radio spectrum for third-generation (3G) mobile communication systems. "I am directing federal agencies to work with the Federal Communications Commission and the private sector to identify the radio spectrum needed for the third generation of wireless technology," said Clinton. "I'm confident that federal agencies, working with the private sector, can develop a plan for identifying the spectrum that will meet the needs of the wireless industry and is fully consistent with national security and public safety concerns."

At the 2000 World Radio Communications (WRC-2000) Conference in Istanbul last May, world governments recommended that 160 MHz be allocated to 3G by 2010. According to an executive memorandum issued by Clinton, the spectrum necessary for 3G for the United States will be allocated by July 30, 2001, with an auction of the spectrum by September 30, 2002. This, of course, raises the issue of where the spectrum will be found. "We face challenges that other countries don't, in that we already have a much more congested use of our bands," said FCC chairman William Kennard. With so many interests—aviation, Department of Defense, public safety, consumers, and the wireless communications industry, among others—competing for a piece of the spectrum, some experts have even predicted an impending spectrum drought, with one of two potential results: either applications requiring spectrum will not be accommodated or the applications will be accommodated but at the cost of RF interference reducing their value.

"I have been warning of spectrum drought in this country if we do not take the steps now to make sure that we are freeing up more spectrum for services such as third-generation wireless," said Kennard. "As the Internet migrates out of the personal computer and into wireless Web-enabled devices, spectrum management is becoming increasingly important."

And there's no shortage of wireless-Internet applications. "Ten years ago nobody wanted to download MP3s over their cellular phones, because they were just happy to be able to make phone calls with the cellular phones, cellular phones weren't as widely used as they are today, and nobody had MP3 players," says Charles Jackson, chairman of FCC's Technological Advisory Committee's working group on spectrum management. "We don't have a drought so much as we have a lot of thirsty mouths out there, and we have to find ways to use the resources more and more efficiently."

Charles Jackson

Traditionally, FCC has increased spectrum efficiency through reallocation, taking spectrum from applications that don't require all the spectrum they currently have—either because they don't use it or because with technical improvements they can use it more efficiently—and assigning that spectrum to new applications. For instance, FCC recently allocated 70 MHz in the 2-GHz range to new mobile satellite services. Julius Knapp, chief of the Policy & Rules Div., Office of Engineering and Technology, FCC, says of the allocation, "That proceeding was illustrative of the difficulties we face today. In order to come up with that spectrum, we had to reduce the amount of spectrum available for electronic newsgathering from 120 MHz down to 85 MHz." FCC also makes available spectrum from the federal sector as the federal government becomes more efficient in its use of spectrum. In mid October, FCC transferred from government use to commercial wireless services 50 MHz in the 3650–3700 MHz band.

Julius Knapp

Another method of improving spectrum efficiency is technological innovation encouraged by FCC policy. "We're trying to encourage and facilitate the introduction of new technology," says Knapp. "For example, in the mobile bands where under the old approach we would have chosen a specific technology and locked it in (more or less what happened with analog cellular), [FCC has] been providing more flexible technical rules, allowing technology to develop and become more efficient." Such new technologies include Bluetooth, ultra-wideband (UWB), and software-defined radio (SDR), all of which show potential for improved spectrum efficiency.

Knapp points to Bluetooth as an example of flexibility in technical rules advancing new technology. Bluetooth operates in the 915 MHz, 2450 MHz, and 5.7 GHz bands under Part 15 spread-spectrum rules. Nowhere in the rules is Bluetooth mentioned. Rather, it was allowed to develop out of the frequency-hopping spread-spectrum rules. And this flexibility has had an effect on emerging 3G, as the success of spread-spectrum rules under Part 15 enabled the implementation of code-division multiple access (CDMA—spread spectrum for both cellular and PCS), which is being incorporated into the 3G system International Mobile Telecommunications 2000 (IMT-2000).

Spectrum sharing is also a possibility for improved spectrum efficiency. UWB needs several hundred megahertz—or even several gigahertz, depending on the system—to function, but there are no longer available sections of unoccupied spectrum of that size. However, instead of monopolizing large sections of spectrum, UWB shares spectrum with an incumbent service by appearing to that service as background noise. Proponents of UWB claim their systems don't cause significant interference to incumbent systems, but incumbents are less optimistic. FCC has an outstanding notice of proposed rule making for UWB and is currently testing to determine interference potential within specific spectrum ranges. UWB also encompasses a wide range of systems with a variety of interference potentials, making it difficult to fit UWB into current FCC regulations.

According to Jackson, another potential option for improved spectrum efficiency is SDR. Rather than requiring hardware replacement in order to operate under different standards such as CDMA, global system for mobile communications (GSM), and time-division multiple access (TDMA), SDR would rely heavily on digital processing of the signal. All that would be needed is updated software, available by download. This could serve spectrum efficiency by allowing the radio device, rather than an operator, to choose the appropriate standard depending on the current level of spectrum congestion and the devices involved in communication. This could also prove especially useful for military applications, as the military currently utilizes a multitude of embedded radio devices, many of which operate under different standards. SDR could allow communication between those devices. The technology is, however, still emerging. FCC is looking at its potential, having assigned the Technical Advisory Committee's spectrum-management working group to the task, and the International Telecommunications Union is including SDR in its IMT-2000 work.

Technical innovation may loosen the belt, but to make the goal of auctioning spectrum for 3G by September 30, 2002, spectrum will have to be reallocated. WRC-2000 identified three spectrum bands that could be used for 3G. FCC will be focusing on spectrum identified in the 2500–2690 MHz band, which is currently encumbered by multipoint distribution services and instructional-television fixed service. And the National Telecommunications and Information Administration will be looking at spectrum identified in the 1755–1850-MHz band, the major incumbent of which is the Department of Defense.

Specific Absorption Rate

Hands-Free Phone Kits Reduce Electromagnetic Radiation

Australia—A recent report concluded that the use of hands-free kits (microphone and earpiece) with mobile phones greatly reduces electromagnetic radiation (EMR) exposure to the head. However, the study also found that wearing the phone on the waist or in a pocket places it and the antenna in closer contact with the body and is likely to increase actual exposure, according to Chris Zombolas, technical director for EMC Technologies Pty Ltd. (Tullamarine, Victoria, Australia). The report also notes that the exposure limits are unlikely to be exceeded when the phone is operated wearing a hands-free kit and holding the phone.

Specific absorption rate was measured using a DASY3.

Recent media reports questioning the benefit of hands-free kits in reducing exposure to EMR prompted the Australian consumers association, Choice, to commission the independent testing of mobile phones with and without hands-free kits. Specific absorption rate (SAR) measurements were performed by EMC Technologies, an independent laboratory accredited for SAR measurements on mobile phones.

Two 900-MHz GSM phones and one 835-MHz AMPS phone were tested. Both GSM phones complied with the Australian and New Zealand SAR limits when tested under normal conditions at the ear position. The New Zealand AMPS phone complied with the New Zealand limit, but did not comply with the Australian limit.

The hands-free kits reduced the SAR inside the head by worst-case margins of 92% for the two GSM phones as well as for the AMPS phone, according to the report. The SAR reduction at the head was achieved when simulating both the handheld and the body-worn positions for each phone. Data indicate that further reduction is likely when the hands-free kit cable is arranged away from the phone antenna, which is generally consistent with normal use.

At the waist position (in hands-free mode), the New Zealand AMPS phone SAR exceeded both the New Zealand and Australian SAR limits. No international standard currently exists for measuring SAR in the hip or waist, the report noted.

Methodology

Because SAR is defined as the rate of absorption of electromagnetic energy per unit mass of biological tissue, the measured SAR for each mobile phone quantified the energy that was absorbed by the body part exposed to the EMR. Each phone was measured with and without the hands-free kit in use. According to the report, the test methodology used was generally in accordance with the mandatory human exposure standard for mobile and cordless phones as specified by the Australian Communications Authority. SAR requirements are specified only for the head.

SAR measurements were taken in the head and torso of the Phantom.

To simulate the human torso, EMC Technologies used a Generic Twin Phantom (Schmid & Partner Engineering AG; Zurich) filled with tissue-simulating liquid. Using a DASY3 dosimetric assessment system (also from Schmid), baseline SAR measurements were performed on the three mobile phones transmitting at full power in the standard left- and right-ear touch positions.

After baseline measurements were recorded, the hands-free kits were evaluated for their ability to reduce SAR inside the head. The hands-free adapters were attached to the Phantom, and the cable was taped along the length of the phone and its antenna to represent worst-case coupling of the EMR to the cable. SAR measurements were then performed inside the Phantom at the ear position with the phone placed 70 cm away from the body to simulate handheld use. Then, with the phone mounted at the flat section of the Phantom, the third segment of the test evaluated the SAR performance of each phone worn at the waist or pocket position.

A copy of the report, including detailed procedures, photographs, and SAR plots, is available from the Choice Web site at http://www.choice.com.au. For more information, contact Chris Zombolas at EMC Technologies Pty Ltd. via e-mail at chris@emctech.com.au or by phone at +61 3 93353333.

Telecom, EMC Experts Join CE Editorial Advisory Board

Barry Cartman

Chris Zombolas

As Compliance Engineering continues to strengthen its editorial advisory board with experts from around the world, BABT's former managing director Barry S. Cartman joins the board, bringing more than 30 years of telecommunications approvals expertise. From down under, Chris Zombolas, technical director of EMC Technologies in Australia, will reinforce the board's electromagnetic compatibility focus, based on his 20 years devoted to this field.

After restructuring BABT's operations following the formation of an international joint venture, Cartman retired to head Cartman dot ORG Ltd., a consultancy that provides interim management solutions to the information technology and telecom sectors. He is also an advisor to the UK Department of Trade and Industry on matters relating to technical compliance and conformity assessment issues that arise from the telecommunications equipment portion of the mutual recognition agreement between the European Union and the United States.

For the last 18 years, Cartman, who holds an MSc and a postgraduate diploma in telecom technology, was an integral part of the major reform of telecom equipment regulation in the European Union. Among his accomplishments was a key role in the management of the European Commission's CTS5 project, which involved the development of pan-European test services for the public-switched telephone network (PSTN).

"My success has been based on my ability to adapt business to change and to understand and respond to complex technical and regulatory issues," says Cartman, who was instrumental in the development of BABT's globalization program, including identifying potential partners worldwide. In addition, he represented BABT as a founding member of the Association of Designated Laboratories and Notified Bodies (now known as the R&TTE Compliance Association), which addresses a range of technical issues surrounding telecommunications regulation.

In his commitment to fostering the transformation of the telecom industry in Europe, Cartman also completed contracts with the European Committee for Electrotechnical Standardization (CENELEC) and the European Organization for Conformity Assessment (EOTC) as an expert for the European Commission's bon-de-commande BC-IT-226. "This group is studying the convergence of the voluntary and regulated test and certification activities of the information technology and telecommunications fields," he explains.

New board member Chris Zombolas is the founder and technical director of EMC Technologies Pty Ltd., an electromagnetic compatibility (EMC), electromagnetic radiation (EMR), safety, and radiocommunications test house in Australia. The company has facilities in Melbourne, Sydney, and Adelaide, Australia, as well as in Auckland, New Zealand.

For the last 29 years, Zombolas has been involved in electronics in the defense, aerospace, and commercial electronics industries, and for the last 20 years, he has concentrated his expertise in addressing electromagnetic interference and electromagnetic compatibility. In that time, he has become an authorized competent body and a European Union designated conformity assessment body (CAB). Zombolas has also been named as a signatory for EMC and specific absorption rate (SAR) for the National Association of Testing Authorities (NATA) of Australia.

"With the CAB accreditation, in conjunction with EMC Technologies' NATA accreditations for testing to all the major harmonized standards, we are now able to provide exporters to the European Union a choice of either the harmonized standards or the TCF route to CE compliance," Zombolas says. "This is so important for marketing electronics products globally."

In his many years in the industry, Zombolas has performed his share of EMI and EMC testing and design to commercial and military standards. Leaving no stone unturned, he has been an EMC design and compliance consultant on EMC in the telecommunications, computer environments and facilities, industrial, aerospace, defense, and medical sectors.

As the EMC representative of the Electrical Compliance Testing Association of Australia, Zombolas is the convenor of the CISPR 11 working group for the standards Australia EMI committee. He is also a member of the Radiocommunications Consultative Committees, advising the Australian government on the implementation of the EMC and EMR frameworks, which focus on EMC issues, including limiting interference to broadcast and mobile signals, and ensuring that critical systems are immune to interference.

FCC to Accept Multiple Countries for Part 68 Certification

In FCC Public Notice DA 00-2290, FCC announced that it will accept applications for multiple factories for Part 68 certification on a single Form 730, even if the factories are located in different countries. Form 484 certificates for applications involving multiple countries will display "MUL" in the country code and "Manufactured in Multiple Locations" in place of the manufacturer's name. The certificates will continue to identify a single registrant company, and applicants are still required to display the product's country of origin on its outside surface (19 USC Section 3109). Additionally, applicants are not required to submit MUL applications and may continue to submit one application per manufacturing location.

All terminal equipment sold in the United States and connected to the public-switched telephone network (PSTN) must be certified under Part 68, which contains specifications designed to prevent harm to the PSTN. For more information on applying for Part 68 certification, contact Jamal Mazrui at 202/418-0069 or jmazrui@fcc.gov.

Elite Expands Illinois Facilities

Elite Electronic Engineering's testing facility is getting a $1 million facelift. The company, which was founded in 1954, is renovating its testing laboratory in Downers Grove, IL, to expand its facilities as well as to enhance its capabilities in its core business segments, including EMC and environmental testing for the automotive and military markets.

New equipment will include a radio-frequency (RF) reverberation chamber, several bench-level test stations, and a CISPR 25–compliant anechoic room for the company's automotive unit. Two RF-absorber-lined chambers are planned for MIL-STD and commercial-aviation testing. Designed for very large equipment, the chambers will be set up with high-power electrical service and HVAC utilities. An additional electrodynamic vibration machine has been added to the company's environmental laboratory.

Slated for completion in December 2001, the renovation includes designated workstations for visiting clients and a new cafeteria for employees. For more information, contact Steve Laya at 800/354-8311 or visit the company's Web site at http://www.elitetest.com.

Esco Acquires Lindgren

Esco Technologies Inc. (St. Louis), a supplier of engineered filtration products and RF shielding and test products, recently acquired Lindgren RF Enclosures Inc. (Glendale Heights, IL). Lindgren, a manufacturer of RF shielding products for the EMC, medical, industrial, and government markets, will work together with another Esco subsidiary, EMC Test Systems (ETS; Austin, TX), a manufacturer of anechoic absorbers, test chambers, antennas, and other test equipment for the EMC, RF-microwave, and wireless markets. Lindgren will continue production of shielding products from its Glendale Heights headquarters.

FCC Clarifies Equipment Authorization for Class B Computers and Peripherals

Now that FCC has designated 17 telecommunications certification bodies (TCBs) capable of reviewing applications for PC-equipment authorization, it will no longer accept applications for certification of computer equipment subject to approval under Declaration of Conformity (DoC). FCC announced in Public Notice DA 00-2224 that, beginning November 1, 2000, applications for certification under 47 CFR 2, for any Class B PC or PC peripheral (including cpu boards and internal power supplies) that can be approved by DoC, must be made to a TCB.

FCC accepted DoC procedures for self-approval in the 1998 proceeding "Streamlining I" (ET Docket No. 97-94, 13 FCC Red 11415 [1998]). Under DoC, Class B PCs and PC peripherals could be approved without filing an application for equipment authorization with the FCC laboratory in Columbia, MD. However, FCC continued issuing certification for manufacturers who chose to have their equipment approved directly.

In "Streamlining II" (GEN Docket No. 98-68, 13 FCC Red 24687 [1998]), FCC approved the use of TCBs, which were authorized, in lieu of FCC, to certify certain consumer electronic devices. FCC indicated that it would cease acceptance of certification applications for these devices once TCBs were in place to process the applications. For more information on Public Notice DA 00-2224, contact Raymond Laforge at the FCC Laboratory, 301/ 362-3041 or rlaforge@fcc.gov.

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