PLEASE NOTE: This document, concerning the Global Positioning System/Ultrawideband Measurement Plan, is a Request for Public Comment. Though it is not intended or expected, should any discrepancy occur between the document here and that published in the Federal Register, the Federal Register publication controls. The paper is being made available through the Internet solely as a means to facilitate the public's access to this document.

Billing Code: 3510-60-P

DEPARTMENT OF COMMERCE

National Telecommunications and Information Administration

Docket No. 000623194-0221-02

RIN 0660-XX09

Notice, Request for Comments on Global Positioning System/Ultrawideband Measurement Plan

AGENCY: National Telecommunications and Information Administration, U.S. Department of Commerce

ACTION: Notice, Request for Comments

SUMMARY: The Institute for Telecommunication Sciences (ITS) and the Office of Spectrum Management (OSM) of the National Telecommunications and Information Administration (NTIA) invite interested parties to review and comment on a proposed measurement plan to assess the potential mechanisms and the extent of any interference to Global Positioning System (GPS) receivers from ultrawideband (UWB) transmission systems.(1)

The GPS/UWB Measurement Plan will be placed on the NTIA homepage at <http://www.ntia.doc.gov/osmhome/uwbtestplan/gpstestfr.htm>. Interested parties may also obtain a copy of the measurement plan from OSM or ITS.

DATE: Interested parties are invited to submit comments on the GPS/UWB Measurement Plan no later than Tuesday, August 29, 2000.

SUBMISSION OF DOCUMENTS: The Department invites the public to submit comments on GPS/UWB Measurement Plan in paper or electronic form. Comments may be mailed to Steve Jones, Office of Spectrum Management, National Telecommunications and Information Administration, Room 6725 HCHB, 1401 Constitution Ave., NW, Washington, DC 20230. Paper submissions should include a diskette in ASCII, WordPerfect (please specify version) or Microsoft Word (please specify version) format. Diskettes should be labeled with the name and organizational affiliation of the filer, and the name version of the word processing program used to create the document.

In the alternative, comments may be submitted electronically to the following electronic mail address: <gpsuwb@ntia.doc.gov>. Comments submitted via electronic mail should be submitted in one or more of the formats specified above.

FOR FURTHER INFORMATION CONTACT: Steve Jones, Office of Spectrum Management, telephone: (202) 482-0110; or electronic mail: <skjones@ntia.doc.gov>; or Randy Hoffman, Institute for Telecommunication Sciences, telephone: (303) 497-3582; or electronic mail: <rhoffman@its.bldrdoc.gov>.

Media inquiries should be directed to the Office of Public Affairs, National Telecommunications and Information Administration, at (202) 482-7002.

SUPPLEMENTARY INFORMATION:

Background

Recent advances in microcircuit and other technologies have resulted in the development of pulsed radar and communications systems with very narrow pulse widths and very wide bandwidths. These UWB systems have instantaneous bandwidths of at least 25 percent of the center frequency of the device. UWB systems can perform a number of useful telecommunication functions that make them very appealing for both the commercial and government applications. These systems have very wide information bandwidths, are capable of accurately locating nearby objects, and can use processing technology with UWB pulses to "see through objects" and communicate using multiple propagation paths. However, the bandwidths of UWB devices are so wide that, although their average power levels, in many cases, are low enough to be authorized under the unlicensed device regulations of the NTIA and the Federal Communications Commission (FCC), some of the systems emit signals in bands in which such transmissions are not permitted because of potential harmful effects on critical radiocommunication services.

The GPS is a critical radiocommunication system. GPS is presently used by aviation for en-route and non-precision approach and landing phases of flight. The Wide Area Augmentation System (WAAS) for Category I precision approach service and the Local Area Augmentation System (LAAS) for Category II/III precision approach service are planned to be available for public use. GPS is also in the final stage of approval as an international aviation standard. Companion GPS-based applications for runway incursion and ground traffic management are also underway. Additionally, GPS-based public safety systems and services are being fielded. Planned systems, such as Enhanced 9-1-1 and personal location and medical tracking devices are expected to be commercially available in the near future. The U.S. telecommunications and power distribution systems are also dependent upon GPS for network synchronization timing. Moreover, GPS is a powerful enabling technology that has created new industries and new industrial practices fully dependent upon GPS signal reception.

Since GPS has such a pivotal role in many critical systems, NTIA has undertaken this measurement program to develop information to evaluate the potential for interference from UWB transmission systems to GPS receivers used for different applications. The GPS/UWB Measurement Plan identifies the GPS receivers to be considered; identifies the UWB transmission system parameters to be considered; proposes a GPS receiver performance metric and criterion; and develops general measurement procedures for calibration and assessing the interference potential.

Questions for Public Comment

Interested parties are requested to submit comments on any of the technical issues in the GPS/UWB Measurement Plan. In addition, comments are requested on the questions below to assist NTIA in refining the measurement plan. Comments should cite the number of the question(s) being addressed. Please provide any references to support the responses to the questions.

1. Are the candidate GPS receivers identified in the measurement plan representative of the different technologies and user applications?

2. Are the UWB transmission system parameters identified in the measurement plan representative of the parameters for UWB transmission systems envisioned for use by the public?

3. Is pseudo-range error a performance metric for aviation GPS receivers that operate in accordance with Technical Standard Order (TSO) C-129a? If so what is the limit on pseudo-range error?

4. If pseudo-range error is not an applicable performance metric for GPS receivers that operate in accordance with TSO-C129a, what performance metric should be used? What is associated performance criteria?

5. Is a performance metric of time to reacquire a satellite applicable to GPS receivers used for terrestrial applications (e.g., public safety)? If so what is the associated performance criteria?



6. A reacquisition time of 1 second has been proposed by at least one GPS receiver manufacturer for terrestrial applications. Due to the latency inherent in the GPS receiver can a 1 second reacquisition time be accurately measured?

7. What are the performance metrics and associated criteria for GPS receivers used for surveying, maritime, and recreational applications?



Kathy D. Smith

Chief Counsel


1. NTIA recently sought public comment on a test plan covering the effects of UWB signals on selected Federal radio receivers other than GPS receivers. See Notice and Request for Comments on Ultrawideband Systems Test Plan, 65 Fed. Reg. 40614 (June 30, 2000). That notice and comments received in response to that notice are also available on NTIA's homepage at <http://www.ntia.doc.gov/osmhome/uwbtestplan/>.