By Topic

Project Relay Digital Command System

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

2 Author(s)
Roth, S.H. ; Astro-Electronics Division, RCA, Princteon, N. J. ; Janes, T.A.

The National Aeronautics and Space Agency (NASA) has developed a coded message sequence consisting of discrete, pulse-duration-modulated (PDM) tone bursts for commanding satellites. The message consists of a sync pulse followed by some combination of six pulses, three each of zeros and ones. This code allows for 20 commands (the combination of six things taken three at a time). This paper describes an equipment developed for the Relay satellite program which demodulates the tone bursts, converts the pulse-duration modulation into a binary code, and then decodes the message into twenty discrete commands. The demodulation and PDM-to-binary code conversion functions are accomplished by conventional transistorized circuitry which is described in a general manner. The circuitry for converting the code into command pulses is a novel utilization of magnetic circuitry and is described in detail. Magnetic cores are used to provide a shift register function and in addition perform the decoding, thus eliminating the conventional diode matrix usually employed for this function. A summary of the physical and electrical characteristics of the finished equipment is presented.

Published in:

Aerospace and Navigational Electronics, IRE Transactions on  (Volume:ANE-9 ,  Issue: 2 )