A doubled Nd:YAG laser is used. Transmission was at 1060 and 532 nm. The 532 nm green wavelength can be seen near the center of the TV screen as it hits the surface in most cases. This is used for ground truth correlation. The spot is about 20 cm in diameter from 100 meters altitude.
Twelve PMT's were used corresponding to the 12 channels of data: Channels 1,2,3,4,9 & 10 have 1090 nm bandpass filters. The reminder are for 532 nm. Channels 9 and 11 have no polarization filters. Relative to the transmitted polarization, the other channels have polarization filters and retardation plates as follows [channel -- filter angle]:
1 -- 90 2 -- 0 3 -- 150 4 -- 150 and quarter wave plate 5 -- 0 6 -- 90 7 -- 60 8 -- 60 and quarter wave plate 9 -- open 10 -- 30 11 -- open 12 -- 120
Master bias PMT bias voltage adjustments may occur for one or the other wavelength, effecting all curves simultaneously. Relative calibration can be made using reflections backscattered from the calibration tarpaulin. Laboratory measurements show both wavelengths have nominal parallel/perpendicular ratios of 0.62 +/- .03.
The principle investigator is Dr. James E. Kalshoven, Jr., NASA/GSFC, Code 925, (301) 286-8506.
FILE TIME COMMENTS (helicopter height)
------ -------- -----------------------------
AFED1 10:33:01 calibration tarpaulin (cal
panal or tarp)
AFED2 10:36:39 - larch orchard
south side of large larches
at seed orchard
AFED3 10:39:31 north side of seed orchard -
2 needle pine
strip closest to road
AFED4 10:43:16 gravel pit- top -
(300 ft.)
AFED5 10:46:12 Bog Site #4 - (up and
down for thermal sensor
from 1000' down)
AFED6 10:54:24 South-most orange tarpaulin on road
near cal site -
maple site - (250 ft.
then rises)
AFED7 11:02:04 next orange tarpaulin,
toward cal site - aspen
(200 ft.)
AFED8 11:05:20 third orange tarp/
birch clump
AFED9 11:09:51 transit - across bog
into woods
(thermal) (500 ft.)
North side of seed orchard
AFED10 11:11:37 top of roof
AFED11 11:15:22 black spruce plantation
(low altitude - 200 ft.)
AFED12 11:17:42 Balloon ( 750 ft.)
Hemlock site
75N 75W
AFED13 11:20:40 Balloon - spruce site
(1000 ft.- 250 ft.)
start at 11:22
AFED14 11:24:49 Big balloon - (300 ft.)
spruce site # 1 -
125N 125W
(no vegetation between trees)
AFED15 11:28:00 Tower (400 ft.)
57 mins. total tape time
St 12:08:08
BFED1 12:11:30 thermal transit -
seed orchard
(500 ft.)
BFED2 12:14:45 road intersection, asphalt
(500 ft.)
BFED3 12:17:53 bog near cal site (500 ft.)
BFED4 12:22:00 cal panel (300 ft.-500 ft.)
CFED1 11:18:04 bog near orange marker sites
(750 ft.)
CFED2 11:22:01 maple site - orange marker
furthest south (500 ft.)
CFED3 11:25:40 marker - aspen site
(500 ft.)
CFED4 11:29:22 grass site - southwest
corner of seed orchard
CFED5 11:31:54 marker at birch site -
(500 ft.)
CFED6 11:35:11 larches - south side - bigger
CFED7 11:40:22 cal panel - (300 ft. - 500 ft.)
CFED8 11:42:43 small bog (500 ft.)
red sphagnum
CFED10 11:45:32 2-needle pine rows
CFED11 11:50:14 gravel - top
DFED1 12:46:00 - not good - test -
DFED2 12:48:11 asphalt road
DFED3 12:52:24 spruce plantation (500 ft.)
DFED4 12:56:07 hemlock site (up to 750 ft.)
quantum sensor on -
no DFED5 -------- visited on ground
DFED6 13:02:58 750 ft. (quantum sensor on)
balloon
DFED7 13:08:30 tower (500 ft.)
DFED8 13:18:04 pond 300 ft. (small)
broke time sequence 13:24 (3 mins.)
DFED9 13:28:12 small pond (500 ft.)
stop at 13:31:15 resumed at 13:43:15
DFED10 13:45:19 large lake (500 ft.)
break - (no DFED 11)
DFED12 13:53:42 river near hanger