sum数据库新测量谱的使用

A NEW MEASURE OF SPECTRUM USE Robert J. MayherRobin H. HainesSteven E. LittsLeslie A. BerryGerald F. HurtCarl A. Winkler U.S.DEPARTMENTOFCOMMERCEC. William Verity, Secretary Alfred C. Sikes, Assistant SecretaryforCommunicationsandInformation AUGUST 1988 FOREWORD This report presents a new and innovative approach to analyzing use of the radio spectrum.The report sets out a framework for a Spectrum Use Measure (SUM) data base which, for thefirst time, joins the technical properties of the radio spectrum to the geographical dimension ina manner that allows for the quantification, measurement and graphic display of how the nation'sspectrum resource is utilized. Further expansion and development of the SUM data base isexpected to lay the foundation for new approaches to spectrum management and promote moreefficient and effective use of the radio spectrum. The radio spectrum is one of this country's most important national and natural resources.Ithasbeenlessthanonehundredyearsthatwehavebeenawareof its usefulness,yettheradiospectrum has been the source of numerous innovations and new industries, all based on theexploitationofthatresource'spotential.Broadcasting,landmobileandsatellitecommunicationsare butafew ofthe services that have been made possible. Spectrum is an invisible resource; it exists unseen around us. Additionally, while technicallyfinite, the spectrum resource has been expanded by the important work of many whose effortshave added to our knowledge of the spectrum's fundamental nature and provided new ways toincrease the intensity of spectrum use. While the physical properties of this invisible resource are well understood by radioengineers,they are substantially less well appreciated by others.Yet it is important that themanagement of this critical resource be carried on in such a way as to render understandableand visible the nature of spectrum use.Costs must be assessed, benefits understood andobjective decisions made. An accurate measurement of what is available and the geographiccosts of aproposed use will better equip us to make the balanced decisions. It is this challenge which NTIA's scientists and engineers have sought to address in creatingthe SUM data base. The essence of the SUM approach is to tie technical measurements ofspectrum use to geography by way of the computerized Government Master File (GMF) of radiofrequency assignments. The result is a tool capable of quantifying spectrum usage in ageographically specific manner. The approach creates a three dimensional information fieldwithina computer,fromwhichwecanplotthe nation'sfixed spectrum resources against itsfixedgeographical boundaries. Using the "denied area" concept, it allows for objective quantificationand measurement of spectrum use in the following ways: Preclusive Use. The SUM data base can measure the amount of "spectrum acreage'used preclusively (i.e., no other use is possible) within a given band and geographiclocation. SikesAssistant Selretary forCommunicationsandInformation Overall, the report represents an important beginning. With all the important issues to be This project could.not have been completed without the special efforts ofa number of individual NTIA staff members. Particularly noteworthy are theefforts of: Charles Schott in providing the initial policy guidance, for theproject; Leslie A. Berry, in defining and developing spectrm use measurementconcepts; Robin H. Haines in fully defining and developing a practicalimplementation of the engineering model and verifying its accuracy; Gerald F.Hurt in elucidating uses of the model in future planning efforts; Carl A.Winkler in providing initial software planning guidance; and Steven E. Littsin developing and integrating new software with existing commercial softwareto provide a working model. Also, the editorial and publishing expertise ofGeorgia (Gigi) C. Chinault and the critical technical review of Paul C. Roosa,Jr. have greatly enhanced this report. EXECUTIVESUMMARY This report describes the Spectrum Use Measure (sUM) data base and model,a new technique for calculating the extent that the radio frequency spectrumis 'used by systems in a frequency band. The suM model performs interferencecalculations using data on existing systems from a frequency assignment fileand produces a data base of spectrum use values for geographic pointsthroughout the region being studied. The suM data base is then used toprepare maps, histograms and indices describing the extent to which thefrequency band is used. The results can be used to show the overall use of afrequency band in a geographic area, to chart the growth in the use of afrequency band over time and to identify uncrowded areas which may beavailable for new assignments. Previously, a standard technique for representing spectrum use was toplot maps showing the locations and connectivity of terrestrial transmittersand receivers. This technique, however, did not quantitatively indicate theeffects of the fre