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Lushbaugh, W. A.

Publications and source records attributed to Lushbaugh, W. A..

Intercomputer Communication Link

Interface units transmit, receive, and perform "handshaking" functions. Two computers communicate over distance up to 6700 meters at average transmission speeds around 200 kilobaud with help of pair of programable interface units. Interfaces use form of pulse modulation and are programed for full "handshaking" capabilities.

Lushbaugh, W. A.

Quicklist: The basis for a computer aided logic design system

Quicklist, a preprocessor for an existing wire list program that cuts the description of the wire list by about 67 percent over previous methods, is described. Quicklist uses two different methods to shorten the input data. The first of these is the use of parentheses to allow a compact way of describing signal names which increment (or decrement) by one, i.e., typical signal names in a bus. The other method used is the equal sign. Using this symbol in a signal list says that the rest of the signals on that chip are the same as those on the previous chip described. Quicklist is intended to be the basis of a computer aided logic design system.

Lushbaugh, W. A.

Preliminary design work on a DSN VLBI correlator

The Deep Space Network is in the process of fielding high-density digital instrumentation recorders for support of the Pioneer Venus 1978 entry experiment and other related tasks. It has long been obvious that these recorders would also serve well as the recording medium for very long base interferometry (VLBI) experiments with relatively weak radio sources, provided that a suitable correlation processor for these tape recordings could be established. The overall design and current status of a VLBI correlator designed to mate with these tape recorders are described.

Lushbaugh, W. A.

Standard interface: Twin-coaxial converter

The network operations control center standard interface has been adopted as a standard computer interface for all future minicomputer based subsystem development for the Deep Space Network. Discussed is an intercomputer communications link using a pair of coaxial cables. This unit is capable of transmitting and receiving digital information at distances up to 600 m with complete ground isolation between the communicating devices. A converter is described that allows a computer equipped with the standard interface to use the twin coaxial link.

Lushbaugh, W. A.

A flexible high-speed sequential decoder for deep space channels.

This paper describes a sequential decoding machine built at the Jet Propulsion Laboratory (JPL), which uses a 3-bit quantization of the code symbols and achieves a computation rate of MHz. This machine is flexible and can be programmed to decode any complementary convolutional code with rates down to 1/4 and constraint lengths up to 32. In addition, metric programmability is provided for optimization of decoder performance with respect to channel parameter variations.

Layland, J. W.

Data compressor Patent

Description of system for recording and reading out data related to distribution of occurrence of plurality of events

Anderson, T. O.

Logic realization of simple majority voting connectives

Redundant circuitry is added to computer network to eliminate incorrect output obtained due to a component failure, noise, or some other disturbance. This circuitry provides majority operation. Only NAND gates are employed, and the modules used are among the most popular microelectronic or integrated circuits presently in use.

Anderson, T. O.