Accession Number : ADA127993


Title :   Modem Signature Analysis.


Descriptive Note : Final technical rept. Sep 80-Nov 81,


Corporate Author : PAR TECHNOLOGY CORP NEW HARTFORD NY


Personal Author(s) : Edwards,Thomas V ; Modestino,James W ; Koligman,Michael B ; Dick,Robert J ; Bartlett,Curry M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a127993.pdf


Report Date : Oct 1982


Pagination or Media Count : 249


Abstract : The objective of this effort was to theoretically and experimentally investigate the use of modem signature analysis techniques for in-service channel-quality monitoring of voice bandwidth channels used for digital transmission. 'Modem Signatures' is a term applied to any characteristic derived from the signal source by measurement or transformation (FFT, for example) for use by a generalized algorithm. Monitoring refers to the determination of the transmission channel condition and, ideally, to the identification of the type and degree of impairments affecting the channel, to aid the operator in effectively managing available resources (channels) and maximizing up-time. Throughout the course of this effort, algorithms effective in the monitoring of in-service voice frequency data lines were developed and demonstrated. A hierarchial approach to performance monitoring was presented and implemented in the form of a demonstration software system. Through demonstration, it was shown that reliable performance monitoring can be achieved for 1200 and 2400 bits/second modems. Not only could the type of impairment be recognized from among Guassian noise, odd harmonic distortion and phase jitter, but the degree of the impairment was also indicated.


Descriptors :   *DIGITAL SYSTEMS , *DATA TRANSMISSION SYSTEMS , *SIGNATURES , *MODEMS , COMPUTER PROGRAMS , ALGORITHMS , FREQUENCY , SOURCES , MEASUREMENT , MONITORING , DEMONSTRATIONS , PERFORMANCE(ENGINEERING) , GAUSSIAN NOISE , TRANSMITTANCE , IDENTIFICATION , RELIABILITY , SIGNALS , DATA RATE , BANDWIDTH , TELEPHONE SYSTEMS , CHANNELS , VOICE COMMUNICATIONS , AUDIO FREQUENCY


Subject Categories : Cybernetics
      Voice Communications


Distribution Statement : APPROVED FOR PUBLIC RELEASE