Multipurpose digital averager provides measurement improvement in noisy signal environments. It provides increased measurement accuracy and resolution to basic instrumentation devices by an arithmetical process in real time. It is used with standard conventional measurement equipment and digital data printers

Naylor, T. K.

Roberts, J. A., Jr.

Schellenbach, R. R.

English

NASA Technical Reports Server

February 1968
	
Brief 68 - 10018 
NASA TECH BRIEF
	
- N 
NASA Tech Briefs are issued to summarize specific innovations derived from the U.S. space program, 
to encourage their commercial application. Copies are available to the public at 15 cents each 
from the Clearinghouse for Federal Scientific and Technical Information, Springfield, Virginia 22151. 
Digital Data Averager Improves Conventional Measurement System Performance 
Data 
Magnitude
__ 
__ 
_
Input Logic Data Summing Display DispIay Selector Decoder Transfer Register jZ Time 
T hreshold
_______
Print 
External Data Ready I	 Reading Reading To Be Output l-.-i- Output	 Command Counter Averaged Encoder References Print 
Hold-Off 
Input Data Hold-Off I	 Minimum 
Sampling
^`To Period
A multipurpose digital averager has been developed 
to provide measurement improvement in noisy signal 
environments. It provides increased measurement ac-
curacy and resolution to basic instrumentation devices 
by an arithmetical process in real time. It is used with 
standard conventional measurement equipment and 
digital data printers. The averager does not introduce 
error to the converted data, but permits precise meas-
urements not normally obtainable by other than clas-
sical filtering prior to measurement and subsequent 
data conversion. 
The general approach used in smoothing the raw 
data is to sum the magnitudes of input digital data, 
count the number of successive readings, and divide 
the former by the latter. The result of this arithmetical 
operation is generated continuously in real time, con-
cluding in a true statistical average value when the 
selected number of readings to be averaged has been 
reached. A selector switch is incorporated' to permit 
input readings to be averaged in powers of 10 covering 
10 to 1.000.000 readings.
In operation, data magnitude is buffered and 
threshold leveled to the logic polarity and amplitude 
required of the input selector gates, which are involved 
in the input truncation whereby 7 input digits out of a 
possible 9 may be used in data transfer and arith-
metical operation. The truncated 28 lines of digital 
data output from the input selector that represent data 
magnitudes from 10 1 through 106 are then transferred 
into the summing register. The data transfer control 
signal is derived from the external digital measuring 
device through . its external data ready command that 
is synchronized at the reading counter. Each external 
data ready positive going step is progressively total-
ized in the reading counter in order to account for the 
preset number of readings to be averaged. 
When the preset number of readings (10 1 to 106) 
has been reached, there will be established as a nu-
merical divisor the preset number available to control 
a gated cloôk for strobing the summing register divi-
dend data, thus producing a quotient or averaged 
value. The averaged value is then encoded in the out-
(continued nvi..'n 
This document was prepared under the sponsorship of the National 
Aeronautics and Space Administration. Neither the United States 
Government nor any person acting on behalf of the United States
Government assumes any liability resulting from the use of the 
information contained in this document, or warrants that such use 
will be free from privately owned rights. 
https://ntrs.nasa.gov/search.jsp?R=19680000018 2020-03-12T05:42:13+00:00Z
put encoder so the data may be displayed by the visual 
in-line decimal readouts, or conditioned for transmis-
sion and made available for digital printer use. 
The minimum sampling period adjustment (T 0) is a 
series of 10 discrete time constants between 0.1 ms and 
40.0 ms which will provide delay between the ntia-
tion of external data ready and the control signal, 
input data hold-off: 
Note: 
Inquiries concerning this innovation may be di-
rected to:
Technology Utilization Officer 
Manned Spacecraft Center 
Houston, Texas 77058 
Reference: B68-10018
Patent status: 
No patent action is contemplated by NASA. 
Source: T. K. Naylor, J. A. Roberts, Jr., 
and R. R. Schellenbach 
of Radio Corporation of America 
under contract to 
Manned Spacecraft Center 
(MSC-12078)
. 
. 
. 
Brief 68-10018	 Category 01


Digital data averager improves conventional measurement system performance

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