Title :
Time Demodulation
Author_Institution :
Formerly, Massachusetts Institute of Technology, Cambridge, Mass.; now, Medicinska Nobelinstitutet, Biokemiska Avdelningen, Hantverkaregatan 3, Stockholm, Sweden
Abstract :
The demodulation of the signals imparted to carriers by the process of time modulation is an essential process of radar range finding, pulse data transmission, and communication. This paper describes methods for precision demodulation which depend upon a time modulator operating in synchronism with the input information, a time-discrimination element, and negative feed-back connections to control the local time modulator to reproduce the modulating signal in an electrical or mechanical form. Accuracies are usually set by the bandwidth of the radio link and may be 5 parts in 104or better.
Keywords :
Automatic control; Circuits; Communication system control; Demodulation; Error correction; Frequency synchronization; Interference; Pulse modulation; Radar; Signal processing;
Journal_Title :
Proceedings of the IRE
DOI :
10.1109/JRPROC.1947.231926