Title :
Use of Subcarrier Frequency Modulation in Communication Systems
Author :
Bliss, Warren H.
Author_Institution :
Assistant Professor of Electrical Engineering, University of Maine; summer vacation period, Terminal Facilities Research Group, R.C.A. Communications, Inc., New York, N.Y.
Abstract :
When subcarrier frequency modulation having a frequency range of 1600 to 2000 cycles was used for transoceanic facsimile transmission, pictures were obtained with finer detail and better half-tone quality than those transmitted by previous systems; the speed of transmission could also be increased. An extension of the system to a two-way multiple-channel radio-relay circuit providing teletype service between New York and Philadelphia gave improved stability of operation when variations in signal strength occurred.
Keywords :
Adders; Art; Circuit stability; Circuit testing; Conducting materials; Facsimile; Frequency modulation; RF signals; Telegraphy; Teleprinting;
Journal_Title :
Proceedings of the IRE
DOI :
10.1109/JRPROC.1943.232033
