AN/GSC-4 DATA MODEM SERVICE TEST MODEL DEV DEVELOPMENT.
Abstract
The Communications Set, Digital AN/GSC-4 ( ), is a flexible full-duplex, compact unit capable of conveying synchronous digital data over telephone voice facilities of nomina 4 kc bandwidth at a maximum of 5400 bits per second. The set utilizes phase shift modulate frequency multiplexed carrier tones, and encodes either 2 or 3 channels of information on each tone in order to minimize the frequency spectrum bandwidth required for high-speed data transmission. Included in the main body of the report are detailed descriptions of the data modem and its various functions and features. A brief summary of the problems areas encountered and their solutions is also given. The results are also included from which conclusions and recommendations are presented. The integral fault isolation equipment greatly reduces down time due to component failures by providing faulty tone isolation almost immediately without the requirement of external test equipment or experienced operating personnel. The modem exhibits error rates of less than 1 x 10 to the -6th power at 28 db signal-to-white noise (white noise power bandwidth of 3 kc0 at 4800 bits per second. Typical 2400 bits per second error rates are in the neighborhood of 1 x 10 to the -6th power at 15 db signal-to-noise ratios. The 5400 bit per second operation generally falls into the 1 x 10 to the -5th power error rate category with signal-to-noise ratios of 28 db. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1962
- Accession Number
- AD0416328
Entities
People
- G. G. Fairbanks
- J. A. Bloor