Ground Targets for SCMS RSF Data Management Group ======================= Work of Rilling and Lee, June/July '91 and of Rilling, June/July '95 The position of about 20 ground targets were carefully determined to allow "ground truthing" of the range and azimuths of all radars during CaPE. These same targets are used during SCMS95. The CaPE area had a very large number of possible ground targets, but an effort was made to limit selection to those that 1) could be seen by more than one radar and/or 2) were in a dual Doppler lobe. Additionally, it was desired to have targets scattered throughout a variety of ranges from the radar. Target positions were determined through conventional use of map, compass, and distance estimates, combined with use of a hand-held GPS (Global Positioning System) unit. Since the GPS positions were determined while Operation Desert Storm was ongoing, selective availabilty was "off", and GPS positions were more accurate than usual. It is likely that GPS measurments were accurate to about 50 meters or less, with map-determined postions having accuracies on the same order. The 1927 North American Datum was used for all determinations (this was the local USGS map datum, and GPS readings were converted for consistency). Twenty one targets are listed in the tables. Others were visited, but not selected for use due to mitigating circumstances such as multiple targets in the same area, or target too broad (this was the case with the KSC Vehicle Assembly Buildings). Targets are listed in two tables, one giving target geographic information, and the second giving ranges and azimuths from the NCAR radar (SCMS was a single-radar project; information for CP4 ranges and offsets have been replaced by corresponding info for the Melbourne NEXRAD, with the unverified assumption that good CP4 targest are good Melbourne targets). Notes follow each table giving information about the suitability of targets for positional determination. Note that towers may not be visible at all with KMLB. This system uses a clutter filter, and possibly a point-target removal algorithm; these may be sufficient to remove any usable evidence of towers. TABLE 1: Target Physical Info Estimated Target Name Height(m) Lat Long (W) ------ ------------------------- --------- ---------- ---------- CP2 NCAR Multiparameter Radar 28:45:18 80:46:26 KMLB Melbourne, FL NEXRAD 34 28:06:47 80:39:16 PAMB NCAR PAM-III Base (approx pos.) 28:36:58 80:57:56 ISS Integrated Sounding Sys (approx) 28:37:28 80:56:33 CP3 NCAR C-band Radar (CaPE, only) 28:20:30 80:56:06 CP4 NCAR C-band Radar (CaPE, only) 28:13:46 80:44:08 T1 Poinsett Lodge 200 28:21:02 80:48:55.6 T2 Deseret Ranch 180 28:18:17.5 80:54:42.3 T3 CP2 NNW (9.5km) 80 28:49:26 80:50:10 T4 Titusville Flda Pwr Light 100 28:36:38 80:48:50.4 T5 Smyrna Beach Apt Twr 60 29:00:19.4 80:52:35.3 T6 Holopaw N (on Hwy 532) -- 28:16:44 81:04:57.5 T7 Melbourne W (SW of 192&95) 70 28:03:56.6 80:43:15.4 T8 Holopaw1 (1.0km S of Hy192) 100 28:08:09.2 81:04:31 T9 Holopaw2 (3.0km S of Hy192) 80 28:07:04 81:04:53.5 T10 Deer Pk, 11km N. 80 28:12:13 80:54:10 T11 Lake Ashby 60 28:57:22 81:05:34 T12 Osteen, NE 150 28:53:15 81:08:43 T13 Geneva 60 28:43:04 81:03:57 T14 Mims 75 28:40:06 80:51:09 T15 Southmere/Aurantia "4" 100 28:39:51 80:55:17 T16 Eau Gallie NW 150 28:08:12 80:42:11 T17a Eau Gallie NW pair 125 28:08:53 80:42:12 T17b Eau Gallie NW pair 125 28:08:58 80:42:14 T18 Lake Pickett #1 485 28:36:07 81:05:36 T19 Lake Pickett #2 515 28:36:12 81:05:11.5 T20 Lake Pickett #3 485 28:34:51 81:04:32 T21 Exit 73 Rest Area 110 28:12:28 80:42:40.2 1) Radar positions from GPS survey of C. Wade, MMM (Feb '91). Verified by Rilling for CP2, Jun '95. 2) Target heights are generally just very crude estimates. Heights for targets 18-20 were obtained from on-site personnel. 3) T1 (Poinsett Lodge) position is somewhat approximate. Tower was located on a dry hump in the middle of a swamp, and was not approachable. 4) T5 is not a good target. It was selected mainly for use to the North of CP2; there is some ambiguity with other possible targets. 5) T6 position may not be entirely accurate. A simple error may have been made in coordinate determination, as this tower often appears as an outlier when range/az residuals are checked for a group of targets. 6) T11 (Lake Ashby) is likely a poor target. An echo was seen in the CP2 data near this location, but it is not certain that this tower caused it. 7) The Southmere/Aurantia targets were 4 towers with a spacing of about 60m between each. Orientation of the line of towers makes it a decent target for ranging from CP2 (but not azimuth checks!). The tower group is not a good target for other radars. 8) The guy wires for the Lake Pickett towers (T18-20) alter the "point" nature of the targets in a radical way. It is estimated that the wires attached to the top of the towers ascended at an angle of about 50deg (elevation angle with respect to the ground). 9) The Lake Pickett towers are generally visible from all three NCAR radars. TABLE 2: Target Relative Positions Name CP2-referenced KMLB-referenced Range Az(deg) Range Az(deg) ---- ------ ------- ------ ------- CP2 N/A N/A 72.102 350.66 KMLB 72.102 170.66 N/A N/A PAM B. 24.25 230.6 N/A N/A ISS 21.93 228.7 N/A N/A T1 45.009 185.18* 30.701 329.02* T2 51.682 195.14* 33.015 310.08* T3 9.757 321.49* 80.765 347.27 T4 16.482 193.76 57.312 344.16 T5~ 29.501 340.17 N/A N/A T6 60.810 209.80 45.885 293.61* T7 76.567 176.11 8.381 231.25* T8 74.697 203.28 41.425 273.50* T9 76.784 203.11 41.969 270.71* T10 62.400 191.67 26.376 292.36* T11 38.277 305.62* 102.814 335.34 T12 39.113 292.05* 98.369 330.76 T13 28.817 261.77* 78.209 328.97* T14 12.299 218.64 64.529 342.49 T15~ 17.581 235.07* 66.446 336.81 T16 68.880 174.22* 5.446 298.72* T17a~ 67.621 174.13 6.174 308.92 T17b~ 67.462 174.17 6.313 309.70 T18 35.534 241.49* 69.189 321.54* T19 34.876 241.19* 68.898 322.06* T20 35.245 236.79* 66.276 321.46* T21 60.959 174.22 11.884 332.04* ~ Targets marked by this symbol are likely not good targets for any of the radars * Indicates that this target is suitable for use with the radar in which column the symbol appears. There may be other targets suitable for use that are not marked, and a user should exercise judgment in selecting those. Notes: 1) Target range/az were determined by use of rectangular coordinates. Care was taken to adjust the coordinate system for the variation in the length of both a degree of latitude and a degree of longitude. The technique used has an estimated error of about 10m in absolute target positioning (larger errors are associated with determination of the tower latitude and longitude).