학술논문

Multiplex Radio Telegraphy and Telephony
Document Type
Periodical
Source
Proceedings of the Institute of Radio Engineers Proc. Inst. Radio Eng. Radio Engineers, Proceedings of the Institute of. 8(6):451-467 Dec, 1920
Subject
General Topics for Engineers
Engineering Profession
Communication, Networking and Broadcast Technologies
Signal Processing and Analysis
Photonics and Electrooptics
Telegraphy
Telephony
Radio frequency
Frequency modulation
Radiofrequency integrated circuits
Transmitting antennas
Tuning
Loaded antennas
Amplitude modulation
Impedance
Language
ISSN
0731-5996
2162-6626
Abstract
The authors classify the chief methods of multiplex radio communication as multi-radio frequency, mono-radio-frequency with multi-audio-frequency, and mono-radio frequency modulated at several super-audio-frequencies each of which is itself modulated at audio frequency. The authors classify antenna systems for the first method as of the series loop type, the branch type, and the mesh type. Each of these systems has zero reactance at a number of radio frequencies. The series type is investigated mathematically for several cases and checked experimentally with good accuracy. Duplex and quintuplex radio telephony and telegraphy over 5 miles (8 km.) at wave lengths around 2,000 meters were experimentally accomplished, and are described.