; ;========================================================================== ; ; FILE: uf_acdoppler.pro ; ; USAGE: result = UF_acdoppler(ufbuf, name [, /OLD]) ; ARGUMENTS ufbuf Buffer of UF words for a dwell of radar data ; name 2 character ASCII name of the data field ; /OLD Use for UF files created PRIOR to January 1996 ; ; ABSTRACT: Return the radial component of the ER-2 motion. This value is ; used to correct the raw Doppler velocity for aircraft motion. ; ; AUTHOR: I. Jeff Caylor ; Science Systems and Applications, Inc. ; 5900 Princess Garden Parkway, Suite 300 ; Lanham, MD 20706 ; ; at: NASA Goddard Space Flight Center ; Code 912 ; Greenbelt, MD 20771 ; Voice: (301) 286-3767 ; Fax: (301) 286-1762 ; Email: jeff.caylor@gsfc.nasa.gov ; ; CREATED: 8 November 1995 ; ; MODIFIED: 29 December 1995 - IJC ; Added /OLD keyword for UF files prior to January 1996 ; and updated ER-2 velocity component for 4th word ; ;========================================================================== ; ; ; For the named field, return the ER-2 velocity value used to correct the ; raw Doppler data for aircraft motion. Units are m/s. ; Error = -1 ; FUNCTION UF_acdoppler, dwell, name, OLD = old velocity = -1 ; ; Get the logical field number ; field = UFfieldnumber(dwell, name) IF KEYWORD_SET(old) THEN BEGIN ; ; If there is a word in the field specific area and the named field ; exists then convert the velocity ; IF (UFspword_size(dwell, field) GE 1 AND field NE -1) THEN $ velocity = FLOAT(dwell(UFspwords(dwell, field))) / UFdatascale(dwell, field) ENDIF ELSE BEGIN IF (UFspword_size(dwell, field) GE 4 AND field NE -1) THEN $ velocity = FLOAT(dwell(UFspwords(dwell, field) + 3)) / UFdatascale(dwell, field) ENDELSE ; RETURN, velocity END