RELIABILITY RESEARCH; CODING CIRCUITRY
Abstract
Study indicated that if the amplitudes of both signal and noise are of Gaussian distribution and if the threshold effect is discounted, there will always be an increase in the average information when the signal power is divided equally among n channels and the noise power in each channel remains unchanged. A threshold value of r sub 1 to the 2nd power = 100 (20 db) was considered necessary to insure an error less than 10 -6 in the case of pulse- code modulation (r sub 1 to the 2nd power is the average S/N power ratio). Cross correlation of pulse trains was shown to be an effective means of overcoming the effects of pulse jamming. The capacity of a channel transmitting binary digits was considered to depend upon the S/N and upon the characteristics of the detection system. An LF pulse source for aligning the pulse-train correlator was constructed with a pulse width of about 1 msec and a PRF of about 80 pps. The output amplitude was variable from 0 to 30 v, and the output impedance was about 300 ohm. A clock-pulse generator was built which will provide 0.1-usec pulses of 0- to 35-v amplitude into a 93-ohm load. The frequency was continuously variable from 200 kc to 5 mc.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 01, 1953
- Accession Number
- AD0009525
Entities
People
- H. L. Stubbs
- J. S. Rochefort
- J. Wiren
- L. J. Nardone
- M. L. Bovarnick
- M. W. Essigmann
- S. H. Chang
- T. P. Cheatham
- W. H. Lob
Organizations
- Northeastern University