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Digital Col1!Munications Techniques and EQUIPMENT for LAW ENFORCEMENT USE and Equipment for Law Enf~Rcement Use

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Digital Col1!Munications Techniques and EQUIPMENT for LAW ENFORCEMENT USE and Equipment for Law Enf~Rcement Use If you have issues viewing or accessing this file contact us at NCJRS.gov. I .t-( J I NBS-GCR-81-356 NBS-GCR-81-356 I DIGITAL COMMUNICATIONS TECHNIQUES Digital COl1!munications Techniques AND EQUIPMENT FOR LAW ENFORCEMENT USE and Equipment for law Enf~rcement Use Urban Sciences, Inc. 5434 King Ave. Pennsauken, NJ 08109 Urban Sciences, Inc. 5434 King Ave. Pennsauken, NJ 08109 January 1982 U.s. Department of Justice . National Institute of Justice January 1982 This document has been re rodu Final Report Fne~~on ~r organization origin~ting i~e~o~~act:y ,as received from the IS ocument are those of th' so view or opinions stated Final Report Issued March 1982 ~~~~~~ent the official position or peolfc~~~o~~ ~~d NdOt' not necessarily . a lonal Institute of Issued March 1982 Permission to reproduce this ... granted by ~~d rnaterial has been -Eubl;c Domain/II S 0 of Commerce r , , epartment to the National Criminal Justice Ref ' F erence Service (NCJRS)-= . .urther reproduction outsid slon of the c~wner. e of the NCJRS system requires perm is- ~ed by the Prepared by the ;DEPARTMENT OF COMMERCE U.S. DEPARTMENT OF COMMERCE )nal Bureau of Standards ''''1!. • Nationai Bureau of Standards ~nal Engineering Laboratory National Engineering Laboratory ~nforcement Standards Laboratory Law Enforcement Standards Laboratory ~ington, DC 20234 Washington, DC 20234 I : I Prepared for the red for the tnal Institute of Justice National Institute of Justice :Jepartment of Justice U.S. Department of Justice lington, DC 20531 Washington, DC 20531 I " , - :), .~- \ \ l '\ ~ ABOUT THE TECHNOLOGY ASSESSMENT PROGRAM FORLWORD 11 J! The Technology Assessment Program is sponsored by the Office of Development, ~ Testing, and Dissemination of the National Institute of Justice (NIJ), U.S. i The Law Enforcement Standards Laboratory (LESL) of the National Bureau of Department of Justice. The program responds to the mandate of the Justice System f Standards (NBS) furnishes technical support to the National Institute of Justice Improvement Act of 1979, which created NIJ and directed it to encourage research and (NIJ) program to strengthen law enforcement and criminal justice in the united development to improve the criminal justice system and to disseminate the results to ! States. LESLls function is to conduct research that will assist law enforcement and Federal, State, and local agencies. t I criminal justice agencies in the selection and procurement of quality equipment. The Technology Assessment Program is an applied research effort that determines the techn,logical needs of justice system agencies, sets minimum performance LESL is: (1) Subjecting existing equipment to laboratory testing and evaluation standards for specific devices, tests commercially available equipment against those and (2) conducting research leading to the development of several series of standards, and disseminates the standards and the test results to criminal justice I documents, including r~tional voluntary equipment standards, user guides and technical reports. agencies nationwide and internationally. .L J il ~ The program operates through: ! This document is a law enforcement technology report developed by LESL under the I sponsorship of NIJ as part of the Technology Assessment Program, which is described ! The Technology Assessment Program Advisory Council (TAPAC) consisting of .... & on the inside front cover' of this report. Additional reports as well as other nationally recognized-crlmInal justice practitIoners from Federal, State, and local 1 documents are being issued under the LESL program in the areas of protective agencies, which assesses technological needs and sets priorities for research { equipment, communications equipment, security systems, weapons, emergency equipment, programs and items to be evaluated and tested. I investigative aids, vehicles, and clothing. i! The Law Enforcement Standards Laboratory (LESL) at the National BUreau of t Technical comments and suggestions concerning this report are invited from all Standards~ich develops voluntary national performance standards for compliance l interested parties. They may be addressed to the Law Enforcement Standards testing to ensure that individual items of equipment are suitable for use by Laboratory, National Bureau of Standards, Washington, DC 20234. criminal justice agencies. The standards are based upon laboratory testing and t evaluation of representative samples of each item of equipment to determine the key attributes, develop test methods, and establish minimum performance requirements for l Lawrence K. Eliason, Chief each essential attribute. In addition to the highly technical standards, LESL also ~ Law Enforcement Stand~rds Laboratory produces user guides that explain in nontechnical terms the capabilities of ",! I available equipment. ,i The Tec~ology Assessment Program Information Center (TAPIC) operated by the International Association of Chiefs of PolIce (IACP), which . supervises a national compliance testing program conducted by independent agencies. The standards I d.eveloped by LESL serve as performance benchmarks against which commercial equ.ipment I is measured. The facilities, personnel, and testing capabilities of the independent f laboratories are evaluated by LESL prior to testing each item of equipment, and LESL helps the Information Center staff review and analyze data. Test results are r published in Consumer Product Reports designed to help justice syste~ procurement 1 offic;l.als make informed purchasing decisions. All publications issued by the National Institute of Justice, including those of the Technology Assessment Program, are available from the National Criminal Justice I Reference Service (NCJRS), which serves as a central information and reference source for the Nation's criminal justice community. For further information, or to register with NCJRS, write to the National Institute of Justice, National Criminal Justice Reference service, Washington, DC 20531. I Paul Cascarano, Assistant Direct.or National Institute of Justice .'.J \ Acknowledgments _.. ,) This report was prepared by the Law Enforcement Standards Laboratory (LESL) of the National Bureau of Standards under the direction of Marshall J. Treado, Manager, Communication Systems Program, and Lawrence K. Eliason, Chief of LESL. The report is based on research conducted by Dr. John Williams and John T. Furze of Urban Sciences, Inc. and updated by William A. Shand, LESL consultant. Acknowledgment is also accorded to the many poliqe departments who provided invaluable information *The points of view expressed in this report are those of the author, and do not during the course of the study. The cooperation received from the digital necessarily reflect the official position of either the National Bureau of Standards communication equipment manufacturers is also acknowledged. This work was sponsored or the National Institute of Justice. Similarly, certain commercial equipment is by the National Institute of Justice, Lester D. Shubin, Standards Proqram Manager. identified by manufacturer and model. In no case does such identification imply recommendation or endorsement by the National Bureau of Standards or the National Institute of Justice, nor does it imply that the equipment identified is necessarily the best available for the purpose. , Preceding page blank iii r), -- -- -':;.J . r' .....1\ \ ABOUT THE TECHNOLOGY ASSESSMENT PROGRAM f , FORLWORD ." The Technology Assessment Program is sponsored by the Office of Development, t Testing, and Dissemination of the National Institu~e of Justice (NIJ), u.S. I Department of Justice. The program responds to the mandate of the Justice System The Law Enforcement Standards Laboratory (LESL) of the National Bureau of Improvement Act of 1979, which created NIJ and directed it to encourage research and Standards (NBS) furnishes technical support to the National Institute of Justice development to improve the criminal justice system and to disseminate the results to J (NIJ) program to strengthen law enforcement and criminal justice in the United Federal, State, and local agencies. States. U:::SL' s function is to conduct research that will assist law enforcement and criminal justice agencies in the selection and procurement of quality equipment. The Techno10qy Assessment Program is an applied research effort that determines the technological needs of justice system agencies, sets minimum performance LESL is: (1) Subjecting existing equipment to laboratory testing and evaluation standards for specific devices, tests commercially available equipment against those and (2) conducting research leading to the development of several series of standards, and disseminates the standards and the test results to criminal justice documents, including national voluntary equipment standards, user guides and agencies nationwide and internationally. technical reports. .~ \ ,1, The program operates through: 1 This document is a law enforcement technology report developed by LESL under the sponsorship of NIJ as part of the Technology Assessment Program, which is described The Technology Assessment Program AdvisorL Council (TAPAC) consisting of on the inside front cover' of this report. Additional reports as well as other nationally recognized crIminal justice practitioners from Federal, State, and local '"', agencies, which assesses technological needs and sets priorities for research documents are being issued under the LESL program in the areas of protective programs and items to be evaluated and
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