DocumentCode
1031920
Title
A 150-Kc Carrier System for Radio Relay Applications
Author
Boughtwood, J.E.
Author_Institution
Assistant to transmission research engineer, engineering department, Western Union Telegraph Company, New York, N. Y.
Volume
67
Issue
1
fYear
1948
Firstpage
577
Lastpage
582
Abstract
The carrier system described was developed by the Western Union Telegraph Company for use with microwave radio relay circuits. Thirty-two voice-band communication channels, each 3,000 cycles wide, are derived in the frequency range 4 to 147 kc. Tandem stages of group modulators maintain a high degree of spectrum efficiency and eliminate the necessity for crystal filters. A crystal-controlled harmonic carrier supply insures the frequency stability required by narrow-band frequency-modulation telegraph circuits.
Keywords
Circuit stability; Communication channels; Frequency; Microwave circuits; Microwave filters; Narrowband; Power harmonic filters; Radiofrequency integrated circuits; Relays; Telegraphy;
fLanguage
English
Journal_Title
American Institute of Electrical Engineers, Transactions of the
Publisher
ieee
ISSN
0096-3860
Type
jour
DOI
10.1109/T-AIEE.1948.5059714
Filename
5059714
Link To Document