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Assessment of Digital Radio Voice Protection for Government Land-Mobile Use

Report ID
TM 87-122
June 01, 1987

This report documents an effort to measure the operational and performance characteristics of radios equipped with the Data Encryption Standard (DES), as applied to government land-mobile operations. The purpose of these tests was to compare selected operational and performance characteristics of the digital (or guarded) mode of operation with those of the analog (or clear) mode of operation for each radio under test. The measurement results are discussed relative to spectrum management issues involving the use of spectrum allocated to the Federal Government fixed and mobile services and the corresponding rules of use. This measurement effort is the first phase of an on-going program to investigate the effect of using digital modulation schemes in a predominantly analog land-mobile environment.