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The Tukey algorithm for enhancing MST radar dataOne of the most troublesome features in MSR (mesosphere stratosphere troposphere) velocity measurements is the determination of unwanted scatterer whose velocity is different from that of the surrounding atmosphere. Aircraft seen in the sidelobes of the antenna are the principal problem. Because coherent integration essentially eliminates echoes with line of sight velocities greater than 10 or 20 m/s, aircraft are seen only when their flight path is almost perpendicular to the line of sight. Then, they give large returns whose velocities may be positive or negative, and certainly different from that of the surrounding air. The glitches in the minute by minute velocity records are quite troublesome in that they may distort the statistics of the velocity. An objective way is therefore needed to remove sporadic points of this kind. For this purpose, the Tukey algorithm is appropriate and has some advantages over averaging. The Tukey algorithm, applied to a data array, uses for each data point the median of it and the two points surrounding it. If the three points form a monotonically increasing or decreasing sequence, the original point is copied with change. However, if the central point is remote from the other two, it is replaced by whichever of the two surrounding points is closest in value. The greatest effect of the Tukey algorithm is on data where the successive points are uncorrelated. Examples are given.
Document ID
19870001088
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Bowhill, S. A. (Illinois Univ. Urbana, IL, United States)
Date Acquired
August 13, 2013
Publication Date
June 1, 1986
Publication Information
Publication: International Council of Scientific Unions, Middle Atmosphere Program. Handbook for MAP, Vol. 20
Subject Category
Communications And Radar
Accession Number
87N10521
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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IDRelationTitle19870000986Collected WorksMiddle Atmosphere Program. Handbook for MAP, volume 20
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