Inside the O.E.T.
The Office of Engineering and Technology (OET) bears the lion’s share of responsibility for helping the FCC keep to its original purpose. Officially, the FCC describes the mission of the OET as “to manage the spectrum and to provide leadership to create new opportunities for competitive technologies and services for the American public.” The OET encompasses the Policy & Rules Division, supported by Spectrum Policy, Technical Rules and Spectrum Coordination branches; the Electromagnetic Compatibility Division, supported by Technical Analysis and Experimental Licensing branches; the Laboratory Division, with its Technical Research, Measurements and Calibration, and Equipment Authorization branches; and the Network Technology Division.
With these resources, the OET is responsible for frequency allocation proceedings, including the reallocation of the 2GHz band for mobile satellite services and broadcast auxiliary services; allocation of spectrum for new broadband, fixed-satellite services in the 12GHz-14GHz band; and reallocation of spectrum transferred from the federal government for use by the private sector. It is also responsible for rulemakings pertaining to Parts 15 and 18 of the FCC rules (47 CFR) that address low-power, unlicensed devices and electromagnetic compatibility. The OET also provides technical advice and recommendations to the other operating bureaus.
The OET not only serves as a resource to other bureaus, but it coordinates in a reciprocal manner with them. It also seeks and researches input from other government agencies, including OSHA, the EPA and the FDA. Entering into the cooperative effort are numerous special-interest groups and industry members, a few of which are the America National Standards Institute (ANSI), the Institute of Electrical and Electronics Engineers (IEEE) and the National Council on Radiation Protection and Measurements (NCRP).
Any rulings made by the FCC regarding spectrum allocation, equipment approval, etc., are, therefore, the result of this wide range of information and knowledge, distilled through the OET. For instance, when the issue of controlling RF emissions from PCs arose, the OET worked with the computer industry to develop measurement procedures and then adopted those into the FCC rules as the method for measuring these emissions. Now that electromagnetic pollution is a hot issue, the OET is working with federal agencies and industry members to augment the OET testing methodology and develop accurate levels and measurement of RF exposure in wireless devices. In this case, the specific absorption rate (SAR), which was adopted by the FCC, was based on an OET review of a standard developed in the private sector.
The OET’s niche
The OET is both active and proactive in guiding industry standards, while being guided by industry acumen. In many cases, an individual or special interest group submits a petition to the FCC requesting a spectrum allocation or a change in a technical rule, and the OET analyzes the request and prepares the relevant rulemakings. In other cases, the commission recognizes the need to modify its rules in response to emerging technologies and initiates rulemakings on its own. Seeing the evolution of a new ultra-wideband technology that operates at low levels over bandwidths several gigahertz wide, the FCC has initiated proceedings to accommodate potential new applications such as ground-penetrating radars and through-the-wall imaging systems based on this technology.
Among industry insiders, and even within the FCC itself, an often-expressed perception is that the OET suffers from a disproportionately larger FCC emphasis on lawyers and economists, with too few engineers and technicians. Some opine that, with more and more communications services being called on to share a finite amount of spectrum, it would be desirable to employ more engineering specialists.
There is, however, some rationale for this division of labor, in that the OET is not fundamentally a research organization, but one that provides guidance to and receives feedback from many levels of government and industry. For the development of standards, the OET does not do a great deal of research or development, but depends on the cooperative efforts of external entities. The budgetary constraints of the past decade make it improbable that this lawyers/engineers ratio will soon change.
Previously, the OET worked with the Wireless Bureau to develop technical rules for new commercial radio services that will operate in the 700MHz band. Licenses for this spectrum are expected to be auctioned in September and in March 2001. The OET played a major role in analyzing technical arguments on the standards for this new commercial spectrum. Based on this analysis, the commission decided to designate a portion of this spectrum as a guard band to protect public safety communications against adjacent channel interference. Commercial services will be permitted to operate in the guard band spectrum, but they must meet strict technical requirements and may not use cellular architectures. The public safety community has also submitted a petition for reconsideration of the requirements, suggesting that the adjacent-channel interference standards may need to be more stringent than those adopted by the commission.
As for the non-guard band spectrum, other petitioners feel that requirements may not be flexible enough in terms of which bands are used for fixed and which for mobile transmitters to allow point-to-point communications. Also, they are requesting higher power output (currently limited to 30W) for point-to-point than was originally designated for mobile transmitters. For example, TRW is interested in having more like 1,000W.
“The OET is focused on determining the appropriate limits on the amount of energy that can be emitted in a public safety band in order to control adjacent channel interference,” Julius Knapp, Chief of the Policy & Rules Division of the OET, said. “In many cases, the answer may be to improve the performance of the public safety receivers.”
On July 25, the FCC adopted a Fourth Notice of Proposed Rulemaking encompassing many of the technical and operational standards recommendations of the advisory National Coordinating Committee it had chartered to define public safety use of the 700MHz band.
The commission established standards for RF exposure about three years ago. The standards for radio equipment are enforced as part of the equipment authorization process. The deadline for compliance with exposure limits is this year. Although most, if not all, cellular and PCS telephones now in use in the United States have already been evaluated for compliance, some hand-held devices were manufactured prior to the ruling in August 1996. Any devices of this nature need to file an environmental assessment with the FCC to determine compliance.
Determination of safe RF levels involves the power radiated by everything from the radio towers to the smallest hand-held unit. Any device used within 20cm of the body must go through SAR measurement procedures, which are guidelines devised by the ANSI/IEEE and NCRP. Although standards and measurements are being studied as an ongoing project by these and other agencies, the interim applicable SAR limit is 1.6 W/kg, as averaged over one gram of body tissue. As issues involving newer technologies, such as the embedded antennas, arise, new studies will continue.
E9-1-1 location testing
Almost all of today’s cellular devices comply with Phase I of the FCC’s accuracy requirements for 9-1-1 automatic location identification (ALI), which states that the cell site or sector where the call is received must be provided. Phase II involves more detailed location accuracies to pinpoint the actual cellular unit issuing an emergency call. For network-based units, the FCC standard is accuracy and reliability within 100m for 67% of calls; 300m for 95% of calls. For handsets, the standard is a bit more stringent: 50m for 67% of calls; 250m for 95% of calls. The obligation of carriers to deploy these technologies, wherever possible, is scheduled to begin in 2001.
According to Knapp, there are advocates of both network-based and handset-based solutions. The key difference is that no handset modifications are required in the network-based method; location is accomplished by triangulation, based on the reception of the signal at multiple cell sites. In handsets, the handset itself incorporates GPS or another means of determining where it is and reporting back to the system.
“The FCC is trying to establish realistic methods of measuring compliance in ALI,” Knapp said. “Considerations in finding representative locations to determine the accuracy of locations are numerous. Should it be an urban area? In areas with tall buildings or lower, high-density structures? What about issues with moving vehicles? How many sites need to be checked in any area to establish accuracy? And on and on… The work for the current policies and rules was done predominately by the Wireless Bureau, consulting with OET. OET is now focused on developing the measurement methods for determining if those standards are met.”
Medical telemetry in the UHF band
In June, the FCC established a new Wireless Medical Telemetry Service (WMTS), based in part on studies by the OET. Medical telemetry devices, such as heart, blood pressure and respiration monitors, transmit patient measurement data to nearby receivers. These devices previously operated on a secondary basis under two sets of rules: a) operating unlicensed under Part 15; and b) operating in the UHF land mobile spectrum at 450MHz-470MHz. Refarming spectrum threatened medical telemetry users operating on an interstitial channel basis on the existing 12.5kHz channels.
The new frequency for WMTS allocated by the FCC is a primary assignment comprising 14MHz of spectrum in the 608MHz-614MHz, the 1,395MHz-1,400MHz and the 1,429MHz-1,432MHz bands. Prior to the creation of the WMTS, Knapp told MRT that “The OET believes that there is possible available spectrum on the television channel 37 (the 608MHz-614MHz band), which is designated for use by radio astronomy, but which remains empty.” (Medical telemetry now has co-primary status with radio astronomy in that band.)
The 1,395MHz-1,400MHz and the 1,429MHz-1,432MHz bands are former government bands reallocated for non-government use by the Omnibus Budget Reconciliation Act of 1993, and their use for telemetry had also been predicted by Knapp. “There is wide acceptance of the proposal for medical telemetry to use these channels during a transitional period until the medical community is able to purchase new devices and shift operations to new frequency bands,” he said.
There had been opponents to the proposal, however. “The satellite community was hoping to use new frequencies for their `little LEOS’ (low earth-orbiting satellites),” Knapp explained. “Also, parts of this spectrum are used for telemetry operations on a secondary basis by utilities for meter reading, etc.”
The land mobile community is interested in what remains of nearby spectrum once the medical telemetry allocation has been made. Therefore, the OET issued a Public Notice to obtain information on the use of spectrum in the 450MHz-460MHz band. It appears that there is no significant amount of use by medical telemetry on that band, which the FCC is now considering opening for refarming to land mobile users for advanced mobile communications.
Intelligent transportation systems
Following the usual pattern of getting an FCC ruling, a private-sector transportation industry group, ITS America, conducted research on what spectrum would be most appropriate for Dedicated Short Range Communications (DSRC) systems that could be used by the transportation industry. Their research indicated 5.850GHz-5.925GHz would be a good choice. They submitted a Petition for Rulemaking to the FCC, requesting a spectrum allocation, and the FCC developed a Notice of Proposed Rulemaking based on that petition. Then, based on responses the FCC received, it decided the proposal had merit and put it into the rules last October, allocating 75MHz of spectrum for Intelligent Transportation Services.
“This ruling represents a wealth of opportunities,” Knapp said. “With DSRC, trucks can be weighed and monitored electronically, with the information relayed by short-range radio to sensors on the side of the highway – a real time and cost savings over the traditional roadside weigh stations. Other applications are electronic toll collection, the measurement of traffic flow along a highway and distribution of information regarding traffic information via highway signs or, potentially, directly into vehicles.”
What’s New, OET?
The new millennium is bringing a new batch of technical terms and concepts to the OET’s attention:
c Ultra-wideband – This technology operates on low levels of power, over wide bands. Among new applications are ground-penetrating radars, which can see broken underground gas lines to detect problems before they explode, and through-the-wall imaging systems that can detect the image of a person in hostage rescue situations or at fire sites. Ultra-wideband devices may also be used for wireless high-speed data devices for use by consumers and businesses.
c Software-defined radios – A new inquiry began in March with an FCC Notice of Inquiry exploring the theory that over the next decade, technology will develop to allow microprocessors in radios to define the characteristics of that radio. Unlike PCS and cellular radios, which are being built to a standard for their specific function, in the future the software within the radio will be able to control the characteristics of the radio signals. Then, if a radio needs to communicate with a TDMA radio, it can operate that way; it can also operate as a CDMA radio, when needed.
“Software-defined radios can help to ease the problem of competing incompatible standards,” Knapp said, “by allowing radios to communicate even if they use different standards. Also, software-defined radios can help solve problems of interoperability. For instance, public safety operates in a number of frequency bands, which frequently makes it difficult or impossible for various law enforcement agencies to communicate with each other. Software radios may allow the same radio, within some broad limits, to operate in multiple frequency bands without a significant cost premium. The FCC has initiated a proceeding for OET to look at this new technology and its implications for spectrum management in solving some of these customary problems.”
Speaking at an industry conference in June, OET Chief Dale Hatfield said that by expressing interest in SDR, the FCC is not departing from a policy of technology neutrality.
“Frankly, as long as other services are protected against harmful interference, we don’t care whether SDR or more traditional platforms win out in the marketplace. Our interest is simply in making sure that our rules do not inadvertently stifle a technology that promises so much potential benefit,” Hatfield said.
“As I see it, the demand for spectrum is potentially so great that we must carefully investigate, experiment with and, where appropriate, adopt all techniques for expanding its availability. SDR technologies – and secondary markets for that matter – are simply one set of tools for accomplishing that goal,” Hatfield said.
Streamlining product approval
To date, 13 private laboratories around the country have applied to the FCC to be designated as Telecommunications Certification Bodies (TCBs). TCBs are empowered by the FCC to certify equipment. Any one of these designated companies will then be able to authorize FCC equipment, a function previously preformed only by the FCC lab in Columbia, MD.
TCBs are accredited in accordance with ISO/IEC guidelines and the appropriate FCC rules. The OET developed the accreditation process with NIST, equipment manufacturers and test laboratories.
“This new system will allow OET’s engineers to spend more time on immediate issues, and the FCC as a whole to focus energies on oversight and enforcement of equipment now on the market,” Knapp said. “Streamlining product approval is an example of the ways in which today’s OET is keeping abreast of the challenges and demands in today’s dynamic telecommunications industry.”
Established in 1934 and directly responsible to Congress, the Federal Communications Commission’s inceptive purpose was to foster “maximum effectiveness from the use of radio and wire communications.” Today, the tasks and responsibilities of the FCC have grown far beyond the expectations of even the most propheticcongressman. Wireless technology in general, and cellular technology specifically, have resulted in spectrum crowding, interference and frequency issues that would have been inconceivable to the rulemakers of the 1930s.
To effectively address this widening range of issues, the FCC today comprises seven operating bureaus, such as Enforcement, Wireless Telecommunications, Cable Services, etc., that are supported by 10 staff offices, including Administrative Law Judges, Legislative, Intergovernmental Affairs and the Office of Engineering and Technology. The staff offices are delineated into numerous divisions, applicable to the staff function, and these, in turn, are usually subdivided into various branches.
Knapp received a bachelor’s degree in electrical engineering from the City College of New York in 1974. He joined the FCC soon thereafter and has held a variety of positions during his 26 years with the FCC. He headed the Frequency Allocations Branch in the late 1980s and was responsible for FCC frequency allocation proceedings for the cellular service, private land mobile services and mobile satellite services. Knapp was chief of the FCC laboratory from 1992 to 1997, when he became Chief of the Policy and Rules Division in the Office of Engineering and Technology. He has had extensive experience internationally on spectrum management and standards matters. He is a member of the IEEE EMC Society and is a Fellow of the Radio Club of America.