Title :
An experimental voice-frequency dialling system
Author :
Toyoda, K. ; Yamamoto, T. ; Nakamura, T. ; Shimada, R. ; Sugihara, K.
Author_Institution :
Fuji Communication Apparatus Manufacturing Co., Kawasaki, Japan
fDate :
11/1/1960 12:00:00 AM
Abstract :
An experimental voice-frequency dialling system is described for signalling between a telephone set with pushbutton caller and timedivision-multiplex switching system, in which the talking path and logical circuit are both time-shared. In order to get good matching between signal-receiving and time-shared logic, single voice-frequency signals sent from a station set are digitally recognized by a periodmeasuring counter in the register without demodulation. The paper discusses some signal-level and noise problems and gives some criteria for system design, together with experimental results. Further consideration is given to frequency allocation, number of cycles and recognition time, and a signal generator is also described.
Keywords :
automatic telephone systems; telecommunication switching; telephone equipment;
Journal_Title :
Proceedings of the IEE - Part B: Electronic and Communication Engineering
DOI :
10.1049/pi-b-2.1960.0059