026247-1 -T MILLIMETER - WAVE RADAR SCATTERING FROM TERRAIN: DATA HANDBOOK Thomas F. Haddock Fawwaz T. Ulaby Radiation Laboratory University of Michigan Ann Arbor, Michigan Technical Report 026247-1-T January, 1990 THE VIEW, OPINIONS, AND/OR FINDINGS CONTAINED IN THIS REPORT ARE THOSE OF THE AUTHOR(S) AND SHOULD NOT BE CONSTRUED AS AN OFFICIAL DEPARTMENT OF THE ARMY POSITION, POLICY, OR DECISION, UNLESS SO DESIGNATED BY OTHER DOCUMENTATION. U.S. Army Research Office Contract DAAL03-89-K-0056

INTRODUCT ION.......................................................................................... 1 II. MMW DATA FOR DRY SNOW.................................................. 6 A. Smooth Surface................................. 7 B. Slightly Rough Surface................................. 10 C. Very Rough Surface................................. 12 D. Heavily Metamorphosed Snow.................................... 14 E Unmetamorphosed Fresh Snow................................... 17 F. Small Crystal Size.................................... 21 G Large Crystal Size.................................... 25 H. Large Crystal Size with Rough Surface................. 27 I. Large Crystal Size with Smooth Surface.............. 31 Ill. MMW DATA FOR WET SNOW................................. 34 A. Manmade Wet Snow.................................... 35 B. Slightly Wet Snow with Smooth Surface.............. 39 C. Wet Snow with Smooth Surface................................ 43 D. Very Wet Snow with Rough Surface........................ 46 E Very Wet Snow with Smooth Surface..................... 48 IV. MMW DIURNAL DATA FOR SNOW.................................................... 49 A. 31 March, 1988.................................... 49 B. 27 February, 1989.................................... 55 C. 2 March, 1989.................................... 59 V. MMW DATA FOR ICE-COVERED GROUND.................................. 62 VI. MMW DATA FOR TREE CANOPIES................................ 64 A. Cedar Trees.................................. 64 B. Red Pine.................................... 67 C. Apple Trees................................... 72 D. Bur Oak..................................... 74 E Spruce Trees................................... 88 F. White Cedar Bushes................................ 91 VII. MMW DATA FOR GRASSES................................. 94 A. Short Grass................................... 94 B. Tall Grass................................... 96

VI II. MMW DATA FOR ROAD SURFACES................................ 112 A. Asphalt...............................112 B. G ravel................................................................................... 117 APPENDIX A. A Millimeterwave Network Analyzer Based Scatterometer................................................................A1 APPENDIX B. Relevant Publications................................ B1 iv

I. INTRODUCTION This handbook provides plots of millimeter-wave (MMW) radar scattering data for terrain based on backscattering measurements made by the University of Michigan's Millimeter-Wave Polarimeter system during the 1987-1989 time period. It is planned to issue an updated version of this handbook in late 1990 that will include additional data acquired in 1990 as well as MMW scattering data reported in the literature by other institutions. Measurements made in 1987 and early 1988 consisted of observations of the backscattering coefficient (o at 35 and 94 GHz. Later measurements included 140 GHz observations as well. Most of the data are presented in the form of plots of Y0o versus the incidence angle 0 for each of the three principal linear polarization configurations: VV, HV, and HH, where H denotes horizontal polarization and V denotes vertical polarization. The radar measurements were often augmented with close-up observations of the target including such measurements as water content and surface roughness, where appropriate. For each data set, a summary of these observations and a photograph of the target scene are provided. The Millimeter-Wave Polarimeter is a mobile truck-mounted radar system capable of making observations from a 20 m high platform at any incidence angle between 0~ (nadir) and 80o. In some cases, however, because of truck-access considerations or signalto-noise limitations, it was not possible to make observations over this entire angular range. Figure 1 shows a photograph of the system in operation and Figure 2 shows a close-up of the antenna platform. Table 1 provides a summary of the present system specifications and Appendix A includes a paper reprint that describes the system operation in more detail, although some of the specifications given in Appendix A are somewhat out of date. No effort will be made in this handbook to provide any analysis of the radar data or to compare the data with model predictions. Instead, a list of relevant publications is given in the bibliography for the interested reader. 1

-Sx - - - ------------------................................................................ F1 1 Photo raph of the MillimeterwWave PolOmeter system with the boom extended 9 9 about half way,,................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... -.............................................................................................-............................................................................................................................................................................................................................................................................................................................................. --.........................................................................................................................................................................................-..........-........................................................................................................................................................................................................................................................................................................................................................................................................................................ 11- 111- 1- 11.111- 11 I.............................................................................................................................................................................................................................................................-............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................... -................................................................................................................................................................................I.......................................................................................................................................................................................................................................................................................................................................................................................................................-.....................................................................................................................................................................................................1-1.1........... -.11I.............................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................11- 11- 1.1- 11- 1...............................................................................................................................................- I''I'll-, ".::,::::,. 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Table 1. Millimeter-wave Polarimeter system parameters. FREQUENCIES: 35, 94, 140 GHz IF BANDWIDTH: 0 to 2.0 GHz TRANSMIT POWER: 35 GHz: +3 dBm 94 GHz: 0 dBm 140 GHz: -4 dBm SWEEP RATE: 1 m-sec/freq., 51, 101, 201, 401 freq./sweep POLARIZATION: HH, HV, VV, VH INCIDENCE ANGLES: 0 to 70 degrees PLATFORM HEIGHT: 3 meters minimum, to 18 meters maximum NOISE EQUIV. ao: 35 GHz: -22 dB 94 GHz: -28 dB 140 GHz: -21 dB CROSSPOL ISOLATION: 35 GHz: 23 dB 94 GHz: 20 dB 140 GHz: 10 dB PHASE STABILITY: 35 GHz: -1 degree/hour 94 GHz: -1 degree/minute 140 GHz: -10 to 50 degrees/second NEAR FIELD DIST: 35 GHz: 2.7 m 94 GHz: 7.3 m 140 GHz: 2.7 m BEAMWIDTH: 35 GHz: R: 4.2 deg T: 4.2 deg 94 GHz: R: 1.4 deg T: 2.8 deg 140 GHz: R: 2.2 deg T: 11.8 deg ANTENNA DIAMETE,-: 35 GHz: R: 6 inches T: 6 inches 94 GHz: R: 6 inches T: 3 inches 140 GHz: R: 3 inches T: 0.36 inches SIGNAL PROCESSING: HP 8510A/8511A based OUTPUT PRODUCTS: -received power verses range -received power verses frequency (at fixed R) -phase and amplitude for each frequency

TERMINOLOGY Average Leaf (or Needle) Dimensions - the approximate main axis length of the individual leaves (or needles). Backscattering Coefficient - radar cross-section per unit area averaged over the illuminated area of the radar footprint, expressed in dB. Also referred to as Sigma-zero or so. Cut - this term is applied to grasses when they have been cut, and no longer have the natural termination on their blades. Data set code - the unique alphanumeric sequence describing each data set. Typically it is the date of the measurement, in the sequence YYMMDD, with a numeric suffix if required for uniqueness. Dry - a material is called "dry" when its moisture content (in the case of soils and vegetations) or its liquid water content (in the case of snow) is within experimental uncertainty of 0 %. Ice Crystal Diameter - the approximate semi-major axis of an individual scatterer. This is typically a statistical quantity, arrived at by examining a number of individual scatterers. Metamorphosed - snow crystals having extensively undergone the natural sublimation process that alters their shape from its original form toward the spherical. Moisture Content - the percent of water, by mass, contained in a representative sample of soil or vegetation. The measurement consists of weighing a sample in its natural state, and again after drying it in an oven. Percent Vegetation Cover - the percent of the ground covered by tree vegetation when viewed from above. Rough - this term is applied to surfaces which are typically rougher than the natural state in which they are usually found. Often, in the case of soils or snow, it is used to describe a surface that has been artificially roughened. 4

Smooth - this term is applied to surfaces which are smooth compared to the natural state in which they are usually found. Sometimes it may be used to describe a surface which has been artificially smoothed. Snow Density - the mass/volume density of undisturbed samples taken from the snowpit. Snow Depth - the distance from the average top level of the snow to the underlying ground. Snow Liquid Water Content (LWC) - the quantity of liquid (nonfrozen) water contained in snow, by weight (gravimetric), measured in percent. Surface RMS Height - the root-mean-square deviation of the surface height relative to the mean surface Surface Temperature - the temperature registered by a mercury-bulb thermometer with the bulb just covered by the top layer of the surface. Tree Density - number of trees per unit area. 5s

II. MMW DATA FOR DRY SNOW Snow is a very complex target and many of the following data sets could be categorized in several ways. In the interests of simplifying the data organization, and facilitating its use by the reader, the data have been categorized into subsections by their most salient feature. The following chart is included in order to give a more complete overview of the characteristics of the data: o o0 8902 0 100 0.~,'- o 0N N o,.. 3 E - 0 Data Set Code A B C D E F G 88029 (S) X x 880329 (SR) x x x 880329 (VR) x x x 890210 x x x 890223 x x x 890302 (SM) x x x 890302 (LG) x X X 890307 (RO) x x 890307 (SM) x x

M"WMW DATA FO DR fY SNOW A. Smooth Surface Dry snow Data set code: 880329(S) Depth: 20-30 cm LWC:0 % Surface RMS height: 1 cm Density: 0.3o to 0.4 gm/cm3 Ice crystal diameter: 1 to 4 mm Surface temperature: - 2.0 C Description: smooth snow surface Surface r Surface roughness profile with I cme grid................................

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MMW DATA FOR DRY SNOW 880329(S) 16.......,... I. 14 Data Set Code: 880329 35 12 Date and Time: March 29, 1988, 5:15 PM 10 Target: Dry Snow 8 Frequency: 35 GHz._.e 6 4 2 or.) 0 -2 - -C.a.....................4 13........................ -6 o -8 -— + W -10. m -12 -14 - --- - HH -16.,........... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Smooth snow at Houghton 16,....,....,....,....,.... 14 Data Set Code: 880329 94 Date and Time: March 29, 1988, 5:15 PM 0' 12 Target: Dry Snow 10 Frequency: 94 GHz.. 8 _- 6 " 0 4 2..-2...'....'.................... 741p 2................... -2 -6 m -8 H -10 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Smooth snow at Houghton

B. Slightly Rough Surface Dry snow Data set code: 880329 (SR) Depth- 20 to 30 cm LWCG 0% Surface RMS height: I cm Density: 0.+3 to 0.4 gm/cm3 ice crystal diameter:. to 4 mm Surface temperature: 0 C Description: snowpack of highly metamorhosed snow with a slightly rough surface Si rge poi w 1 *s y.. x...................1 sss __ I11 11 EE. ss s-... s............. s~g

MMW DATA FOR DRY SNOW 880329(SR) 12.......,.... I. I..,.... I.... a... 1 0 Data Set Code: 880329 35'm.Date and Time: March 29, 1988, 5:15 PM ~. 8 Target: Dry Snow Frequency: 35 GHz,.2 4 o 2....................-4 m ~-86 t~~~ -*..K@@-e~~~-@~ I-H-....... +......... o -6..........a....... V H -8 -10. 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Slightly rough snow at Houghton 14 Data Set Code: 880329 94 c 12 Date and Time: March 29, 1988, 5:15 PM 10) Target: Dry Snow 1. 80 E Frequency: 94 GHz 8.- 60 4 2......................... -2..... -4 3 -6................ VH -8 1 0 3 -10 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Slightly rough snow at Houghton 11

C. Very Rough Surhaee Dry snow Data sot code: 880329(VR) Depth:- 20 to 30 cm LWG: 0% Surface RMS height: 4 cm Density:- 0.3 to 0.4 gm/cm3 Ice crystal diameter:, I to 4 mm Surface temperature:. 0 C Description: snowpack of highly metarmorphosWu snow witha rough surface Surface............... rouhnes.pofie.wth.cm gri.......................................................

MMW DATA FOR DRY SNOW 880329(VR) 14 12 ~ Data Set Code: 880329 35 10 _ Date and Time: March 29, 1988, 5:15 PM Target: Dry Snow 8 Frequency: 35 GHz 6 D 10 2...,... OVr 2o r -4 +- - W o -6......_ -8 -10. I.........'....''... -10 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Very rough snow at Houghton 16 14 - Data Set Code: 880329 94 i 12 Date and Time: March 29, 1988 10 Target: Dry Snow 10 Frequency: 94 GHz 8 I..~~~+.. -2:01..36 -41 o -6 13

D. Heavily Metamorphosed Snow Dry snow Data set code: 890210 Depth: 27 cm LWC: 0, %o Surface RMS height: — 1 cm Density: 0.5 gm/cm3 Ice crystal diameter: 2 to 4 m m Surface temperature: - 48 C Description: heavily metamorphosed snow 1mm 1.4 XDomini,,S'djl _ f t000 W: N f S - I:1~~~~.

MMW DATA FOR DRY SNOW 890210 SNOW PIT PROFILE FOR 890210 temp. (deg C) top 2221 20- -4.8 19 18 17 1615- -4.0 14 Eo 13 4 12a, 1110- -3.3 9 5 - -2.1 4 3 2 1 -0.8 bottom air temperature: -4.4 C 15

MMW DATA FOR DRY SNOW 890210 10 F..........,' ~ "' ~..,..,.. 8. Data Set Code: 890210 co Date and Time: February 10, 1989, 1:40 PM n0, 6 Target: Dry Snow Frequency: 140 GHz O 2 -2 - -' 1... co -1 W- - - -12 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Snow at Brighton 16

LWG~~ ~~~ (at 2:1 PM) 0:: %::: Surface~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~: tepraue 4: C: ~ ~ Sr ce: roghes proil withll-. 1:: cm grid 1~~~~~~~~~~~1

8 90 22 3................ ~~~~~~~~~~~~~~~~~~~~~~~~~~~..............f ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~............................... _.... ~~~~~~~~~~~~~~~~~~~~~~~~~~~................... _ s - * |'l~~~~~~~~~~~~~~~~~~~~~~~l; 0 0~~~~~.......:~~~~~~~~~~~~~~........:: ft.....................7..i;00000E'00 i~E~..... -... -:..... 000000:;00E.........2"'.'...:0 SS....-'R S................0j.:E iiE~EE:: E:: i-.............'".i...RE TH.iE R.i........................................................~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~:E T~iifiRE.,:-',.E'','-.'..:-'E EERREiEE'TE.............................................................:::.........0:00:........00ii000 R;:SR,...~~~ ~ ~ ~ ~.................................;0.00000 0........ 0...:-:- -...................~~ i...R00000 0 00..-.;........~i:020002000.:g.....:. -..-.................... t~~~~~~~~~~~.......................................000000.......:.....f t; 00 - -................... ~.....;..... i;. t0 f Et;000 iE 0 f00:..................................... i; - -......................... 000000 00000000................0000000000000000000000000;Lg~g:::000-0000000000-;00. —:: - - 0 *,........... t F::....... t:0 Rl.:ssS>S.9 R=R:-SS9~~~~~~~~~~~~~~~~......................... ^ _ S::t MX::::::::::::::::::::::::~ ~ ~ ~~ ~~ ~~ ~ ~ ~ ~~~~~~~~~~~~~~~~~~...............................................~.................; SS,9:S,0>yR B w... i:: ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.................R...::.....::::.S S i-::~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~~..................~i.BSB ~ *..>N ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~ ~~ ~~ ~~ ~~ ~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~........,-.,s,.-::hiR i: i':: i' S-:iS00.:BA'::VR.,~~~~~~~~~~~~~~~~..........................:- ~ ~ ~ ~ ~ ~ ~......:.:.::......:

MMW DATA FOR DRY SNOW 890223 10 10.......... I..... I... I.....I..... I..... I.. F.. 8 Data Set Code: 890223 co 6 Date and Time: February 23, 1989, 11:35 AM " 4 Target: Dry Snow. 2. Frequency: 35 GHz 2 o 0 -2 C0 -4 - 6...............'............-.......... -8 -14 - —. — HH -16 -18.. I 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Dry snow at Brighton Data Set Code: 890223 __ 6 Date and Time: February 23, 1989, 11:35 AM Target: Dry Snow Frequency: 94 GHz o o -2 -4................... -6 ~ -8 m -10 —. —- -IHH -12.....I I I I I I 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Dry snow at Brighton 19

MMW DATA FOR DRY SNOW 890223 10........., Data Set Code: 890223 ~' 8 Date and Time: February 23, 1989, 11:35 AM Target: Dry Snow 6 Frequency: 140 GHz 0_ 0 0 2 ~0 o -2 + W.... e' -4......... Cu.2 -60r 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Dry snow at Brighton 20

F. Smait Cryst-al Si~ze Dry s~nowXData set:code" 8903032(SM) De~pth* 1 0 cm LWCI. 0 % Surface RIMS height, 0,15 cM D~n sity:* 0.1 to 0 2 adm/CM3 ie crystal dianle.ter* M..M; Surface temperature: -5 0 Description: smoot~h snow S ufC-e........._1_................................:..............:.......... EE EEE....... RiSiR....... E~E E E E -: EE ~iR iE~ ~iE E~E iE~ ESiH R EE ER R iE E E EE~EEiEiE~iiEE i~ ~E~ilg EE R~ ~.~ERREER....:....:R:: iRTiEREEEEEEEEEElEE.....00 0 00:S~g.......................0000:j...... EE~~EEEE~...... ~ iEEEEEEE..E.........E EiEEEEE igEE~~~~~~~~~iEEEEEEEEEE: -:: iR igEEE:0000000000000000000000002000 i ~~~ ~ ~ ~ ~.....................................R...EERi...i EE iE~E ~~ERiEEEEi~EE~..........:::::::::.::::::::::::::...:::::::::::::::.................E....................EE..................:.EE..REER...iE R..R...E.................................. 00:0:0 =:g:00:: 0:0::00.EES:0000.........ER E ~..............ES.....................................:::::::::::::::::::.:::::::::::::::................E EERR~~EE:~~:::~::~~~:Eii:iiiiiiiii~~~~::::~~~..........E~EREE...........................~ERiSE~i.................000.............::::::::::::::::::...............000 0....................................0:::::g:;002.....................00.....-..........................................~~~~~~~~~~~~~~~~~~~~:::00::::0................ 0:000000...:00.. 0000:00000000 0000...........pr-71 w th 1 c~ g e....................~~~~~~~~~~-n

MMW DATA FOR DRY SNOW 890302(SM)..t......mm ~i!!! i ii!~!~: i'I~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~AT ~~~~~~~~~~~~~~~~~~~~~~~~~i i'.:~..............~..........~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...?i~::ii::'"":~:~:::i::.~i~:~:~!~i~!!!~::!?....~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.......................~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~..... Snow crystals from surface Snow crystals from bottom of: snowpack................ -Bej2 2

MMW DATA FOR DRY SNOW 890302(SM) 10 8 Data Set Code: 890302-sm m 6. Date and Time: March 2, 1989, 9:55 PM Target: Dry Snow 2 0 -2 O -4 O -6. -8........................... -10 (U -12 -14 - WVV c -16................- VH -18 HH -20 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Small snow crystals at Brighton 10 Data Set Code: 890302-sm -m Date and Time: March 2, 1989, 9:55 PM Target: Dry Snow 6 Frequency: 94 GHz 4) 0 O 22 )-4'6... ~. I. ~.!~...~~~~ 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Small snow crystals at Brighton 23

MMW DATA FOR DRY SNOW 890302(SM) 10 Data Set Code: 890302-sm m " 8 Date and Time: March 2, 1989, 9:55 PM Target: Dry Snow 6 Frequency: 140 GHz 4 0 2 C. 2ar mo -2 \.......... 2.......HV................. -4 -6 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Small snow crystals at Brighton 24

G. Large Crystal Size Dry snow Data set code: 890302(Lg) Depth: 10 cm LWC: 0 % Surface RMS height: 0.15 cm Density: 0.1 to 0.2 gm/cm3 Ice crystal diameter: 2 to 2.5 mm Surface temperature: -5 C Description: fresh smooth snow surface 890302(LG) 12,,, 10 Data Set Code: 890302-Lg Date and Time: March 2, 1989, 6:45 AM m 88 Target: Dry Snow 6 Frequency: 35 GHz 4 o -2 -4 m -6 -14 -16.. -18. a I I A 1I it I I A a I I I I I I I A1: Ia.... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Large snow crystals at Brighton 25

MMW DATA FOR DRY SNOW 10.......... Data Set Code: 890302-Lg 8 Date and Time: March 2, 1989, 6:45 AM Target: Dry Snow 6 - Frequency: 94 GHz.5r 4 2 0 _3 - -0- -............................._=.................. m -6 " __- HH - -8 P -2 -4leeeeeIncidence Angle (deg rees) L -6 -8I I 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Large snow crystals at Brighton 890302(LG) 12 10 Data Set Code: 890302-Lg m0 LDate and Time: March 2, 1989, 6:45 AM 8 C Target: Dry Snow Frequency: 140 GHz "'" 6 O Large snow crystals at Brighton

H. ~Large Crystal Size dwith Rough Surface:Dry snow Data set code: 890307(ro) Depth: 1 0 cm LWQ:Q0% Surface. R MS height: 1.17 cm Density: 0.4 gm/cm3 Ice crystal diameter:. 2 to 4 mm Surface temperature: -10 to -12 C Description: dry slightly metamorphosed snow Surface roughness proFile with 1 cm grid:7~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~......

MIMW DATA FOR DRY SNOW 890307(RO) B:: E E igE:i ii:-: i:::<:::-: i i Ti.:. igE.2 i E -.. i i i s.:*.i:E.i: iif ii -:i~i~i022 iiiiii- iiii —:ig iiii - i iigi: i-Ei7:giiii:::: t.0 ii -......:::::::::::::: >'1>t't ~ ffi............................: "';:'~:'':ii'ii sx::>,.:,: w s:.::.: ~ \:: i:~i:;;i~i:i-iiii: 3....................::.4: 333 -- - —:Ig:: j::-a a iiii:E:i — E:iiii:i —:::: -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~:::::i i::: h'i~~~:~~..iiii~~i~iiiiiii~~iiiiiii~?: >...: w. tiiii~i:i~ii~ie::iiiiiiii i.:............................: ~~~~~~~~~~~~:::~~~~~~~~~~~~~~~~~~~~~:::_:i~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~:::~ ~~~~~~~~~%:'....... 3 | ~~~~~~~~~~;-::::::f;::..ss __s::0;: i:::___:,::g000 i;h:.;::::::-:;::i: —':,B X -i'" 3 -::::: B: _ -: -::i3Si::,:, S0 i; t0;::: t~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~-i:::_:~ m & _00 g.:,S:B; -:: Snow- crystals from surface

MMW DATA FOR DRY SNOW 890307(RO) 10 Data Set Code: 890307-ro.m 8 Date and Time: March 7, 1989, 6:00 PM 6 Target: Dry Snow Frequency: 35 GHz 0 4 r,. 0 C -2.,,- _ _-4 Q)~, ~.................I.-. VN m_ -8.- H,-10 Incidence Angle (degrees) Dry rough metamorphosed snow at Brighton 10 8' Date and Time: March 7, 1989, 6:00 PM'O Target: Dry Snow 6 =Frequency 94 GHz 0 -4.- w 4 0. 0. O..~Q~............... HV -6 -8 1 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Dry rough metamorphosed snow at Brighton 29

MMW DATA FOR DRY SNOW 890307(RO) 10 10 W.. I,.W. *..... I..... I..... Data Set Code: 890307-ro m 8 v Date and Time: March 7, 1989, 6:00 PM Target: Dry Snow 6 Frequency: 140 GHz 44 rc -2 i............... HV 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Dry rough metamorphosed snow at Brighton 30

MMW DATA FOUH UIY nn wwvv.Large Crystal Size with Smooth Surface Dry snow Data set code: 890307 (Smn) Depth: 10 cm LWC 0 % Surface RMS height: 0.28 cm Ice crystal diameter: 2 to 4 mm Density: 0.4 gm/cm3 Surface temperature': 10 to -12 C Description: dry slightly metarnorphosed snow 1Chiliiiii::* ORE!,.!:C:i:~::;isstRsBpshwar.............

MMW DATA FOR DRY SNOW 890307(SM) 10 8 _ Data Set Code: 890307-sm - Date and Time: March 7, 1989, 6:00 PM 6 Target: Dry Snow Frequency: 35 GHz.)e- 4 2 0 -................. m -8 H 10 I I.... i....... 4 — 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Dry smooth metamorphosed snow at Brighton 10 n. - 6...,. T w. W.................[]..... Data Set Code: 890307-sm 8 Date and Time: March 7, 1989, 6:00 PM m -2 -s Target: Dry Snow 4 m L~ - ~~ -- f HH 0 1 0 20 30 40 50 60 70 80 Incidence Angle (degrees) -2 0 -..,.... o -6 HV 32

MMW DATA FOR DRY SNOW 890307(Sm) 10..... 8 Data Set Code: 890307-sm m' L Date and Time: March 7, 1989, 6:00 PM P 6 Target: Dry Snow Frequency 140 GHz CQ 1.., 0 -62 8....................... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Dry smooth metamorphosed snow at Brighton 33

III. MMW DATA FOR WET SNOW As in the previous chapter on Dry Snow, the following chart is included in order to give a more complete overview of the characteristics of the data: Cut: ~ >o "'Data Set Code A B C D E 890220 x 890309 (vw w/rs) x 890221 x 890309 (vw w/s s) x 890215 x 34

MMW DATA FOR WET SNOW A. Manmade Wet Snow Wet snow Data set code: 890215 Depth: 27 cm LWC: (at 3:25 PM): 8.,82 % Surface RMS height: 1.6 cm Density: 0.48 gmI/cm3 Ice crystal diameter: 2 to 4 mm Surface temperature: 0.0 C Description: man'made wet snow................................ in; — b Snowmakng scen................... 6.................................... ~ ~ ~ ~ S o m kn....................

IVMW DATA 1FOR W.T:SNOW:: —:: -:::::-' —-:: s'::s,x:::: fsxx<Ms::si Sgggx>B0&..::->B...-::-:>::.:.:- >X.-_ X _11 S | g | 9 0 | lX 9>l~~~~~~~~~~~~~xg Sgg:l:::.......................................... f. >.9Sgg & = = _ _ _ |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-:-::::-:::.. -..-_::_::::: -. s<>,gBS>g:7gi:::; 0:: _ Surface roughness profiie vuth 1 cm grid e |' uilalX tlt,|!,!, E E ~, | ~~ > tlll:::::000::00000::::0002020:0 -::::... - gB~~~~~~~~~~~~~~~~~~~~~~~~~~~xB BgB S~~~~~g 9 9g~~~~~gB~~g S. g Bx x9 — - x gx g~i~~i~:::::ii~- B g:: I m':'iiiiiii'::i'i'i' 1S i: fF"0J!;ll~'~:i i i~igEEiiEiifEEifglig000-Et EESE: ffg E:i~E E~i- fEVE iM0E0iiEEEigiELEaifgE20ElEEE~iEEEEEEl!\E ei 00000 I ~ ~ ~'::~~-:::::::::::::::::: -:::'::: i:::::::::::: f:::: Data collecton scene~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~'-:: 36i..~c

MMW DATA FOR WET SNOW 890215 16.....,, I.. *. *. I'''..... 14 1 2 Data Set Code: 890215 10 Date and Time: February 15, 1989, 11:30 AM 10 Target: Wet Snow c Frequency: 35 GHz *X 6 4 *~ 2 0 t..) 0 m -2 -4 -6 -8 - -10 -12 -14 -16 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet snow at Brighton 4.........,.....,,,, 2 Data Set Code: 890215 m 0- Date and Time: February 15, 1989, 11:30 AM - 2 - Target: Wet Snow 4 s Frequency: 94 GHz c -4 -6 -8 0 -10 -12'"~~~~~e -~~~~,...,14.................... -14 ~ "-16 + W vv... -18..... -20 -—' —- 1HH -22 -24... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet snow at Brighton 37

MMW DATA FOR WET SNOW 890215 8 6 Data Set Code: 890215 nm 4 t Date and Time: February 15, 1989, 11:30 AM 4 Target: Wet Snow C 2 Frequency: 140 GHz o 0 o -2_ -- - -4 kC..... X- -6.l" -8 -+- VV -10.........o....... HV m -12 HH 14................................... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet snow at Brighton 38

B. Slightly Wet Snow with Smooth Surface Data set code: 890220 Depth: 6.5 cm LWC (at 2:08 PM): 0 % LWC (at 4:23 PM): 1.88 % Surface RMS height: 0.11 cm Density: 0.1 to 1.0 gm/cm3 Ice crystal diameter: 1 to 2 mm Surface temperature: 0.0 C Description: smooth, wet natural snow SNOW PIT PROFILE FOR 890220 temp. density to p 665 _ (deg C) (g/cm3) 0.0 0.113 x 4- -0.25 0.237 3- 0.237 3~~39 ~ 2 -0.25 i - 0.958 (ice) bottom air temperature: 1.1 C 39

M;MW DATA FOR WET SNOW GL,~~~~~~~~~~~~~~ wse~~Daa olooloo_ 0gil;E00 f EE iEiE.EjfgESSEE-iE~ERiE0l!REE000Eg~~kglE~l~fj!fEgEW; E0 f0! iER j 0 it. E0fE E Sl000000000000000WiC00000000000000000-00000000000000000000000000000000000000000000000i~00000000t0 t~tti;:0000000t t0000:tt Snow crytls from surfae X., t t tE~t~40

MMW DATA FOR WET SNOW 890220 Data Set Code: 890220 co Date and Time: February 20, 1989, 12:45 PM 2 Target: Wet Snow Frequency: 35 GHz 0 -2 0 0 -4. -6 -8. -10 3 -12 -14 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet snow at Brighton 2 Data Set Code: 890220 rm Date and Time: February 20, 1989, 12:45 PM Target: Wet Snow -2 Frequency: 94 GHz -4 -6 ) -8 -12....... W -o4 t W -161 co -18 — "* — HH -20 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet snow at Brighton 41

MMW DATA FOR WET SNOW 890220 4 _ Data Set Code: 890220 m ~ Date and Time: February 20, 1989, 12:45 PM ~ 2t2 Target: Wet Snow Frequency: 140 GHz 0- - - - - -2 o c -4 -6............... -.' -8 a -12 - ----- HH -14...., 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet snow at Brighton 42

I~~~l~~~i jiji~~~~~~~jjljiji~~~~~~~~ijijjjiji~~~~~~~~~~i~~~iiiiiiiiii~~~~~~~~~~i:::::::::::::::i~~~~~~~~~~~~~~~~~~~illliiiii:::::iiiii~~i!~!ii;i~;liiiii!i:iiiii!!~iiii~!iiiii!!iiiiji~!jiiii~iiii.!!ijii!iii~~ii!iijiiiiiiii!!~iiiiiiiiiiiiiiiiiiiiiiii.. iji~~~l-il —::ll::::: i;:-l-l I::i -:j::;liiii:ii:iii:iiijiijiiiijijiiiii:iiiiiiiiiii:iiii!!;i;iiiiiii~:diiii C ~' 0 0~~~~~~~~~~- 0 o -J~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~I — o 0.( "0_ <:D; D a "0 T c.c.i-crmrcCO cg-. ~3 — OC)O.)0 ~ 0~~~'~_..~ ~~~~ ~~ ~ ~ ~ 3'ClN3. -' 00 ~~~~ cji'~' 0 0 ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~ 0:C~ 00 ~ ~.~i':~~~~t It:h:i-: ~:~:~:::~:~:~:~:~!! ~ ~ ~ ~ ~ ~ ~ ~ S

MMW DATA F:OR WET SNOW ta cogl lectio seen.Ci00 iA_~4

MMW DATA FOR WET SNOW 890221 8... I........ I..... I..... i..... 6 ~ Data Set Code: 890221 m 4 Date and Time: February 21, 1989, 11:40 AM n 2 Target: Wet Snow c. 0 ti Frequency: 35 GHz -2 - * -4 O -6 _ \ m -8 -10' m -12 -14 -18 -20 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet snow at Brighton 2.......................... Data Set Code: 890221 Date and Time: February 21, 1989, 11:40 AM _ -2 Target: Wet Snow -6 -4.....Frequency: 94 GHz o -10-18t..............-............................................ m -20...,..,.,.,..o...i... -22 - 16 _ -24 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet snow at Brighton 45

D. Very Wet Snow with rough Surface Wet snow Data set code: 890309(RO) Depth: 4.0 cm LWC (at 2:30 PM): 16.89 % LWC (at 3:09 PM): 15.47 % Surface RMS height (sample 1): 1.36 cm Surface RMS height (sample 2): 1.78 cm Surface RMS height (sample 3): 1.79 cm Surface RMS height (sample 4): 2.29 cm Surface RMS height: 0.15 cm Density: 0.42 gm/cm3 Ice crystal diameter: 2 to 4 mm Surface temperature: 4 to 6 C Description: rough, wet snow 890309(RO) 6 Data Set Code: 890309-ro m 4 Date and Time: March 9, 1989, 12:15 PM 2 Target: Wet Snow Frequency: 35 GHz o -2 - -4 o -6 O -8 c -10 @-12 T'a' "'x'-......-..,.,,,,,,. m -12 -....... -22,~~~~~~.................................................. -14' ~~~~~~~~~~~~~~"""~............ v -16 a.~4 O~~~ VV.............. -18 e........ m VII............... -20 - - ~- - HH -22..., i, 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet rough metamorphosed snow at Brighton 46

MMW DATA FOR WET SNOW 10,u[..... I,,,, Data Set Code: 890309-ro' 6 - Date and Time: March 9, 1989, 12:15 PM 4 Target: Wet Snow c 2 F Frequency: 94 GHz a) 0.o -4 0'~ 1 2~iT e.......................................... ~ a -10 6...H*. m -12 m -14 -+ W m -16 -, — HH -18 -20 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet rough metamorphosed snow at Brighton 890309(RO) 10........ I.. I... 8 Data Set Code: 890309-ro m Date and Time: March 9, 1989, 12:15 PM 6 Target: Wet Snow Frequency: 140 GHz o 4 ~, - 2-2 c o. m -8 -10..... I -- I I 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet rough metamorphosed snow at Brighton 47

E. Very Wet Snow with Smooth Surface Data set code: 890309(sm) Depth: 4.0 cm LWC (at 2:30 PM): 16.89 % LWC (at 3:09 PM): 15.47 % Surface RMS height: 0.30 cm Density: 0.42 gm/cm3 Ice crystal diameter: 2 to 4 mm Surface temperature: 4 to 6 C Description: wet, smooth snow 890309(SM) 8... * *, * * * * * I *'' W',''''' I''''' I''''' ['''' i''' [' I 6 Data Set Code: 890309-sm Date and Time: March 9, 1989, 12:15 PM 2 Target: Wet Snow 0 - Frequency: 35 GHz Z -2' -4 O -6 -8. -10 -12,~ -i6 16..................... -18 W m.........,....... -20 -22 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Wet smooth metamorphosed snow at Brighton 48

IV. MMW DIURNAL DATA FOR SNOW A. 31 March, 1988 Snow Data set code: 880331 Depth: - 71 cm LWC: 0 to 10.2 % Smooth surface RMS height: 0.49 cm Slightly rough surface RMS height: 0.88 cm Very rough surface RMS height: 1.98 cm Density: surface: 0.39 gm/cm3 15 cm depth: 0.50 gm/cm3 30 cm depth: 0.54 gm/cm3 45 cm depth: 0.53 gm/cm3 6r cm depth: 0.58 gm/cm3 71 cm depth (ground): 0.65 gm/cm3 Ice crystal diameter: 0.5 to 1 mm Surface temperature: -2.7 C to 4.5 C Description: metamorphosed snow divided into three sections, one natural surface (smooth), and two with roughened surfaces 12 Data Set Code: 880331 ground truth 8 Date: March 31, 1988 4'X 3O,..... —.' -4 -I-+ LWC -8.........o....... Air temp (~C) --- I- Snow temp (~C) -12 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) 49

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Surface roughness profile of very rough snow Snow crystals from su~rf-ace! ilI~~5

MMW DIURNAL DATA FOR SNOW 880331 10 8 Data Set Code: 880331 35 Date: March 31, 1988' 6 Target: Dry Snow Frequency: 35 GHz _. 4 Incidence Angle: 400 oC.'"' 2 0 C.) 0 0) C -2 -4 Cu O.) -6 Cu 4 W VV -8 -10 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) Houghton snow with smooth surface 10.. I I I 8 Data Set Code: 880331 35 Date: March 31, 1988 6 Target: Dry Snow Frequency: 35 GHz 4 Incidence Angle: 400 O C.) C'2 0 0) -4 C:u~- -4 e.) -6 c -8 -10 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) Houghton snow with slightly rough surface 52

MMW DIURNAL DATA FOR SNOW 880331 10 8 Data Set Code: 880331 35 Date: March 31, 1988 6 Target: Dry Snow Frequency: 35 GHz._.e 4 Incidence Angle: 400'- 2 C -2 -4.C -6 -- VV m -8 -10 I I I,, I,, 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) Houghton snow with very rough surface Data Set Code: 880331 94 8 Date: March 31, 1988 c 6 Target: Dry Snow Frequency: 94 GHz 0 4 4 Incidence Angle: 400~ ~ —' 2 C) o 2......3........ - 0.................... = -2 -4 +. - VV.z.-6................ VH 0 m -8 — H —- H 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) Houghton snow with smooth surface 53

MMW DIURNAL DATA FOR SNOW 10 Data Set Code: 880331 94 Date: March 31, 1988. 6 Target: Dry Snow Frequency: 94 GHz _ 4 0 Incidence Angle: 40~0 4) = 2 o 0 1 3.. o 0......~ ~.: q....'......a......... m -2 V \.*.' -4 ma 4 —--- VV U = -6 ao. o-....... VH m -8 -10 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (hours) Houghton snow with slightly rough surface 12,,,..,,.-,.,..., ~ *... Data Set Code: 880331 94 10 Date: March 31, 1988 -o 8 Target: Dry Snow Frequency: 94 GHz 6 Incidence Angle: 400 4) -4 6 o 2 -2'a.D. ~.d -6. VH..... m -8' HHI 54

B. 27 February, 1989 Snow Data set code: 890227/28 Depth: 9.5 cm LWC: 0 to 5 % Surface RMS height: 0.1 cm Density: 0.31 gm/cm3 Ice crystal diameter: 1 mm Surface temperature: 0.0 C to -9.0 C Description: partially metamorphosed snow 890227/28 SNOW PIT TEMPERATURE PROFILE (oC) Time 1400 14451 54 01655 180011900 2100 2302 0100 030010 500 0605 0803 9.5 Top 9 0.0 2.0 -4.0 -3.5 -6.5 -6.5 6.3 -8.5 -9.0 -7.5 -7.0 8 0.0 0.0 6 aL 5 -0.6 -0.3 -0.3 -0.5 -1.1 -4.0 -5..5-54.0 -5.0 -6.5 -4.5 -5.7 4 3 bottom -0.6 -0.7 -0.6 -1.0 -0.6 -3.6 -4.0 -4.0 -3.5 -4.5 -5.5 -3.5 -3.8 air temp -3.5 - 3. -3.2 -5.1 -8.5 -8.0 -6.8 -6.5- -10. -11. -9.2 -7.0 55

MMW DIURNAL DATA FOR SNOW 8 9-0 2:2 7/2:8 9 Data Set Code: 890227/28 8" * Date: February 27-28, 1,989 7 Target: Snow - 6'.-' -410 1t 2 Time (hours) Liquid water: content during snow' diurnal at: Brighton Surface roughness profile with 1 cm grid.56

MMW DIURNAL DATA FOR SNOW 890227/28 2 Data Set Code: 890227/28 0 Date: February 27-28, 1989 m -2 Target: Snow Frequency: 35 GHz -4 -6 Incidence Angle: 40"- = -8 -10 6.,, - -128 -14 o-t -16 -18 d e -22 -30 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 Time (hours) Snow diurnal at Brighton 20''''''' 16 Data Set Code: 890227/28 Date: February 27-28, 1989' 12 Target: Snow 8 Frequency: 94 GHz Incidence Angle: 400 4 /t" -8 -12 0 -16 0 -20 co - 0................ HV -24 — _-_ — iHH -28..a I.. Ia,. I I 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 Time (hours) Snow diurnal at Brighton 57

MMW DIURNAL DATA FOR SNOW 890227/28 16..,...,~.-' ~.,. ~ ~ ~ Data Set Code: 890227/28 m 12 Date: February 27-28, 1989 Target: Snow 8 Frequency: 140 GHz c Incidence Angle: 400 e 4 = o o _ m -82 t W- - VV 0 -8............................ -16 10 12 14 16 18 20 22 24 26 28 30 Time (hours) Snow diurnal at Brighton 58

C. 2 March, 1985 Snow Data Set code: 890302 Depth: 10 cm LWC: 0% Surface RMS height: 0.15 cm Density: 0.1 to 0.2 gm/cm3 Ice crystal diameter: 2 to 2.5 mm Surface temperature: -4 C to -5 C Description: partially metamorphosed snow SNOW PIT TEMPERATURE PROFILE (OC) Time,0400 050010600 0700 0800 0900 1000 1100 1200 1300 1400 1500 1600 Top 1 0 - -4.0 -5.0 -5.0 -5.0 -5.0 -4.0 -4.0 -3.0 -3.0 -2.0 -2.0 -2.0 -1.9 95 8 7 6 5 — 7.0 -7.0 -6.0 -6.0 -6.0 -5.0 -4.0 -3.0 -3.0 -1.5 -1.0 -1.8 -1.7 4 bottom -13.0 -11.0 -10.0 -10.0 -8.5 -6.0 -4.0 -1.0 -1.0 -0.5 -0.0 -1.5 -1.5 air temp -15.0 -13.5 -13.0 -12.0 -10.0 -6.0 -5.0 -5.0 -5.0 -3.5 -4.0 -4.5 -5.0 Time 1700 1800 1900 2100 1400 1500 1600 1700 1800 1900 2100 Fop 1 0 — 2.8 -3.7 -4.0 -5.0 -2.0 -2.0 -1.9 -1.9 -3.7 -4.0 -5.0 9 8 E 7 7 6 5 -2.3 -2.7 -3.1 -3.5 -1.0 -1.8 -1.7 -1.7 -2.7 -3.1 -3.5 4 3 bottom -1.8 -2.0 -2.2 -2.5 -0.0 -1.5 -1.5 -1.5 -2.0 -2.2 -2.5 air temp -5.5 -6.0 -6.5 -7.5 -4.0 -4.5 -5.0 -5.0 -6.0 -6.5 -7.5 59

MMW DIURNAL DATA FOR SNOW 4 I I I Data Set Code: 890302-diurn 2 Date: March 2, 1989 Target: Dry Snow 0 -Frequency: 35 GHz Incidence Angle: 40~ -2 a -4 -. o t-, -6 t -"X'" -10'"......... -2...........-....-.. VH m -12 -14.. a'' a. I 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (Hours) Snow diurnal at Brighton 10 Data Set Code: 890302-diurn 8 Date: March 2, 1989 Target: Dry Snow 6 Frequency: 94 GHz.0 [ Incidence Angle: 40~ 4 4 0 O 2 0)E e,,.............. q a.~' *......'. / Y -2.. + r 0 -4................. HV -6''''. 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (Hours) Snow diurnal at Brighton 60

MMW DIURNAL DATA FOR SNOW 890302 8 I.i....''.. "' I... I i.. I.. I... I,, i I,,, Data Set Code: 890302-diurn 6 Date: March 2, 1989 -o Target: Dry Snow 4 Frequency: 140 GHz.e Incidence Angle: 400 -2 2Y 0 mo 06 ~..........._ -2 (,,) -8 co -6................. IN 0 2 4 6 8 10 12 14 16 18 20 22 24 Time (Hours) Snow diurnal at Brighton 61

V. MMW DATA FOR ICE-COVERED GROUND V. MMW DATA FOR ICECOVERED GROUND Data set code: 880308 Depth: 3 to10 cm Surface RMS height: 1 mm Surface temperature: 0 C D0escription: ice formed by the freezing of sheetP flooded terrain, about!0% of the surface was covered by pools of water Ice covered ground 62

MMW DATA FOR ICE-COVERED GROUND 880308 4......... I''.' 0 Data Set Code: 880308 ~m Date and Time: March 8, 1988, 2:32 PM ~, -4 Target: Ice Covered Ground Frequency: 35 GHz C' -8 o -16 -20............... t -24 C s 1 -28 -+ W - -32.......... VH m -36 - - - - HH -40.. 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Ice Data Set Code: 880308 $ -2 Date and Time: March 8, 1988, 2:32 PM Target: Ice Covered Ground E -4 Frequency: 94 GHz U_ -6 O 0) -8 C ~ -10 -12 - W -14.....,. J...... -14 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Ice 63

VI. MMW DATA FOR TREE CANOPIES A. (}edar.T'reees Cedar trees [)ata saet c(t:de: 871 "1 11 Tree density: 0.07 treesn2 Average leaf (or needle) dimttsions:r....< 2 to 3 cm..Leaf moisturt.e conternt: - 70 % Ground cover roisture content: ~ $.35 % Percent vegetation cover: 90 % Percent cover of undergrowth: 1 00% Mloisture content of utndergrowth' 35% Description: Stand of mature oak trees over o:iw ground cover.. 2M -, 03 tM Cedar trees 1_SliI~~~~~~~~~~~~~~~~~(l

MhOW DATA F:OR THEE CANiOPIES ByE II F: ~ ~. _ A -::::::: - _:iaii:: 0.;E t 0..- it:.. 1|11|11 - 3i~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~isb Needles if Cedr-articees... ~ ~ ~ ~ ~ ~ ~ ~ ai;i-..~iPeraaaa~ii j <.000 -,.~~~~~~~~~~~~~~~~~~~~~~~~~Wi3N~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~: Ground c-V0 enahCed: re

MMW DATA FOR TREE CANOPIES 871111 2 m ~ t Data Set Code: 871111 03' -2 Date and Time: November 11, 1987, 9:18 AM -2 Target: Cedar Trees r -4 - Frequency: 35 GHz - -6 O -8 c -10 -12 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Cedars at Arboretum m -16 2 Data Set Code: 871111 Date and Time: November 11, 1987, 9:18 AM! 0 Target: Cedar Trees Frequency: 94 GHz -2 -4 0 0 -6: -8 " -10 -12,=, -r.+ W m -14 -16.... I,., A 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Cedars at Arboretum 66

B. Red Pine 5 -11 November, 1987 Data set code: 871105 Tree density: 0.14 trees/mn2 Average leaf (or needle) dimensions: 10 to 15 cm Leaf moisture content: -70 % Percent vegetation cover: 90 % Percent cover of undergrowth: 100% Moisture content of undergrowth: 35% Description: Stand of mature red pines over dry, fallen needles 1 G0 M 1 M Red pines 67

.Mi~~~Nneed esof e ins

8 71 10 5 4.. I I I I V I I I I 1 I I ~~ 0 Data Set Code: 871105 Date and Time: November 5, 1987,'12:01 PM Target: Pine Trees -4 Frequency: 35 GHz -8 0 o -12 -16 (44 0 1 0 2 0 3 0'0 5 0 6 0 7 0 8 C Incidence Angle (degrees) Red Pines at Arboretum (5 November, 1987) 2 V IFT-V — v V I.. 0 Data Set Code: 871107 -2 Date and Time: November 7, 1987, 10:59 AM Target: Pine Trees -4 Frequency: 35 GHz.2 -6 o -8 -10 -12 -14 ~-16 (4 1~ W ~-18 -20o..II..... 0 1 0 20 30 40 50 60 70 80

2 0 Data Set Code: 871107 co ~Date and Time: November 7, 1987, 10:59 AM -2 Target: Pine Trees Frequency: 94 GHz -4 0 -6 0 C) -8 00 ~-12 ~-14 -16-18 J 0 1 0 2 0 3 0 4 0 5 0 6 0 7 0 8 0 Incidence Angle (degrees) Red Pines at Arboretum (7 November, 1987) 8 71 1 09 2 1 W I a I a I I I I I 5 a I I 1 1 F 0 Data Set Code: 871 109 co ~Date and Time: November 9, 1987, 2:20 PM -2 Target: Pine Trees Frequency: 94 GHz.~-4 * -6 0 -8 0 -10 * 12 co -14 -f- -16.I. t..I -...*... 0 10 9, 20 3 40 50 60 70 8 0

4 *. * I. * W' I... I I * -. I *. I -. *. I.. * I -.. * Data Set Code: 871 1 10 m 0 Date and Time: November 10, 1987, 9:24 AM'_~ Target: Pine Trees _. -4 Frequency: 35 GHz C U q, -8 0 o -12 7c -168-......................... 0 10........... 30................. co o -20 13 co 4, o -0....... od: 7111R o 8_ e 20 W m -28................ VH -24 -28......... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Red Pines at Arboretum (10 November, 1987) 871111 4 0 Data Set Code: 871111 RP Date and Time: November 11, 1987, 1:43 PM -4 Target: Pine Trees Frequency: 35 GHz -8 -12 0 q,. o -16 -20 co -24 w 16~~~~~~~~.1.......r 20 30...... 5 6 70 0 c2 12]........nc.dence.Angle (degrees) ~,~ ~~~1 Noebe,197.~ 4- W~~~~~~7

C Apple Trees Data set code: 880811 Tree density: 01 trees/m2 Average leaf (or needle) dimensions: 4 by 8 cm Leaf moisture content: 80 Percent vegetation cover: 90 Percent cover of undergrowthc 100% Moisture content of undergowth:3.5 m 2 m 0.5m Kf _.:.......... I.:a'.......-i! -N

: F.:' R" TR.X:: E::iB+ MMW DATA F CANOPIE _ g I — - I l l 1 l | | | 1 11 I | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ —----------------- *. _ I _ - S I | l | | I 1 l 11 1E | | ~~~~~~~~~~~~~~~~~~~~~~~~~................ $081 11|U:0111 0;v _a S 1Co 801 Date.d;Time: A:grr 1 ~ 1 9:..... 5 AM....Ap e... Fr; wee p A 0Hz~.......... V~ ~ ~'A' ~~~~~~~~~~~~~~~~~~I;).............. 000fE:L eaves of pp:,e t~ree 8aio 1: 11

D. Bur Oak Bur Oak (Quercus macrocarpa) Data set code: 880930-1 027 Tree density: 0.09 trees/rn2 Average leaf (or needle) dimensions: 8 by 12 cm Moisture content of undergrowth:..70% Percent cover of undergrowth: 1 00% Percent vegetationcover: 95% Description: Stand of mature oak trees over low ground cover ~7M -'4M -1 M 80 Z?70 60 0 *50 40 o 40 20 9/30 1 0/4 1 0/1 3 1 0/1 4 1 0/1 5 1 0/2 7 11/18

Bur oas ak t Botanical Gardens 8809..... V% ~~~~~~880930 Le:ve-s of: Bur oa ks -,at ot nicai ard0n s 880930..'7:'5.

MMW DATA FOR TREE CANOPIES.....................~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.........||E.iij~~il: —::~ | 10 | _ } rId n 8:::::::::::-:::::::::: a::::::::~.....::..............,'":::! aS | l || || -.......... ~ ~ ~ ~ ~ i:i-:~::_::::::...........S _ _ ai ~s a _: sa' 00 I I I_|111 l a s. isZlas 10'i g3111 I _|1 11 | | 11 __ iX: —~"'~"8a~% l~s~isn ~..: Leav~~ ef Bu-f oaks t Botafiscai Garderns v 8j

.............. Bur~~~~~~~~~~~ oa s at Bo'tan'l ar0 ns8 0

M MW DATA F:OR T RE E C ANO P!E S ~~~~~~~~~~~~~~~~~~~~~~~~~~.................................................................,,~.:..~;4 ~......~...~.. Gro~~~~~~~und ~ 0,ove be:ahuroks at Bot a ncaIG rdrs.......... ad ns 8 1 2 Le v e. s~ ~ ~~~~~~~~~~8:0:'

880930-1 027 2. I. I. I i I. I. I I I I. I..I 0 Data Set Code: 880930-1027 _' Dates: September 30 -- October 27, 1988 n0, -2 Target: Oak Trees Frequency: 35 GHz -4 Incidence Angle: 200 o -6 o0 -8 O -10 -12 -14 -20 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 DAY 0 Data Set Code: 880930-1027 "a_:Dates: September 30 -- October 27, 1988 -2 - Target: Oak Trees Frequency: 35 GHz -' 4 - Incidence Angle: 300 -6 O -8 * -10 -12 U) + W m -14 -16',''''.,'.. *' *. *... *.'''. *' -16 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 DAY Bur Oaks (Quercus Macrocarpa) 79

880930-1 027 4 I I I I I I I. I., I. I I I Data Set Code: 880930-1027 0 Dates: September 30 -- October 27, 1988 m Target: Oak Trees -4 Frequency: 35 GHz -8 IncidenceAngle: 700 -12 0 o -16 -20..... []...............C]...0................[3 1-..1....*a......... -24 co... VV 0 x -28 o................. IV ~0 m -32 — H- I -36.... 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 DAY Bur Oaks (Quercus Macrocarpa) 6 "' I "I I i I ~ I' ~ I ~ I ~ I ~ I' I " I ~ I'~ I 6~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Data Set Code: 880930-1027 Dates: September 30 -- October 27, 1988 2.. 2 Target: Oak Trees Frequency: 94 GHz 0 Incidence Angle: 500.4 -2 /2 0 -4 -6 -8 o -10 0 -12' + W -14 HHt -16 a I 0 -1 a I I I a I I I a I a I a I a, I I 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 DAY Bur Oaks (Quercus Macrocarpa) 880930-1027 80

Data Set Code: 880930-1027 4 0 Dates: September 30 -- October 27, 1988 Target: Oak Trees 0 Frequency: 94 GHz u -4 Incidence Angle: 70 -) O -12 2o -16o HV = -20......... -24 co................. IN m -28 -—,- - HH -36 0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 DAY Bur Oaks (Quercus Macrocarpa) 880930 6, " I ~!'' ~ Data Set Code: 880930 m 2 Date and Time: September 30, 1988, 11:53 AM 0 ~ Target: Oak Trees -2 Frequency: 35 GHz -4 -6 o -8 -10 m -12 0 -14 a -18 - 0 -20 t -22 -24 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) Leaf Moisture Content = 59.7% 81

881004 O.... I I'. I'., I... [,... "... I... a I. I, I a. I a I I I I. Data Set Code: 881004 m -2' Date and Time: October 4, 1988, 12:05 PM Target: Oak Trees Frequency: 35 GHz * -4 q.. o -6 r' -8 -10 m -12 -14..... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) 4 - Data Set Code: 881004.a 2 Date and Time: October 4, 1988, 12:05 PM -~ 2 Target: Oak Trees 0 Frequency: 94 GHz )0 -2 -4 O -6 -8 -10' -12..... * -14 ut......... la........H o -16 -18 -- HH.'. -20..... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) Leaf Mositure Content = 54.2% 82

881013 6 Data Set Code: 881013 Date and Time: October 13, 1988, 12:14 PM 4 Target: Oak Trees.2. Frequency: 94 GHz 0 -2 - 0 -4 -6 a -.................... -8........ o -10 w - 1..........a....... VH m -14 - -- H -16.... *.... 0 10 20 30 4 0 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) Leaf Moisture Content = 63.4% 881014 4 i I I I I Data Set Code: 881014 m 0. Date and Time: October 14, 1989, 1:40 PM -2 Target: Oak Trees -4 - Frequency: 35 GHz -6'4- -6 -8 0 -10 O -12 c -14 ~ -16 B- uVV Oa w.....a co -18. -20................ HV -22 2 -24 -26.. I I 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) Leaf Moisture Content = 50.1% 83

881015 6..........,' I''''' I''''' I,,,,,' 42 Data Set Code: 881015.m -2 Date and Time: October 15, 1988, 12:30 PM Target: Oak Trees -2 - Frequency: 35 GHz 0 -4 0 -8 *..i ) -10 m, -12 -14 -16 -8 -.. 0 -10 20 3 4-0 0708 -22 -24 -26 0 10 20 30 40 50 6F0 7n0 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) 4 Data Set Code: 881015 co 2 Date and Time: October 15, 1988, 12:30 PM 0 Target: Oak Trees Frequency: 94 GHz * -2' -4 o -6 m -1 Z -12 -14 + w -16 -18 -20.........,, 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) Leaf Moisture Content = 55.2% 84

881027 2 Data Set Code: 881027 m 0 Date and Time: October 27, 1988, 1:00 PM Target: Oak Trees -2 -,...Frequency: 35 GHz -4 -6 o -8 -10 -: -12 -14 0 -16 -18_ W -20 -22......... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) 4. IV I. I I v - w. r w w I I,. u.,.... Data Set Code: 881027 Lm Date and Time: October 27, 1988, 1:00 PM Target: Oak Trees H -4 Frequency: 94 GHz -8 O -12 c I1 [..................... -16 - " o -20 m -24 -28........ 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Leaf Moisture Content = 42% 85

881118 4....................... 2 Data Set Code: 881118 mo Date and Time: November 18, 1988, 11:42 AM X, 0 Target: Oak Trees Frequency: 35 GHz -2, -4 O -6 -8 m -10 -14.........0............... C -16 - - - - H -18....'.... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) Data Set Code: 881118.o 0 - Date and Time: November 18, 1988, 11:43 AM Target: Oak Trees 0 - -2 [ Frequency: 94 GHz O -4 o -6' -10.....,, 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Bur Oaks (Quercus Macrocarpa) Leaf Moisture Content = 27% 86

881118 4 _ Data Set Code: 881118 Go Date and Time: November 11, 1988, 11:43 AM Target: Oak Trees, — I Frequency: 140 GHz 0 0 C: -4 -6 - <..' - VV -8 -10..... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Oaks (Quercus Macrocarpa) Leaf Moisture Content = 27% 87

E. Spruce Trees Spruce (Picea abies) Data set code: 881031/881122 Tree density: 0.03 trees/m2 Average needle dimensions: 2 cm Leaf moisture content: 53.1%(881031); 56% (881122) Percent vegetation cover (est.): 80 % Percent cover of undergrowth: 100% Moisture content of undergrowth:35% Description: stand of mature spruce trees with weedy ground cover..................... 0. Spruce tree $8

MMW DATA FOR TREE CANOPIES 881031 4 Data Set Code: 881031 co 0 Date and Time: October 31, 1988, 1:23 PM Target: Evergreen Trees -4 _ Frequency: 35 GHz -4 ~ -8 O -12...............................................................a ~ -16 0 + —-- WVV 0 -20 -2................ VH -24, 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Norway Spruce (Picea Abies) 4 - Data Set Code: 881031 la 2 Date and Time: October 31, 1988, 1:23 PM Target: Evergreen Trees' ~ 0 Frequency: 94 GHz.0. -2 o -4 -6 O) -1................ HV m -14 -16. 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Norway Spruce (Picea Abies) 89

MMW DATA FOR TREE CANOPIES 881122 4' 4 m 2 Data Set Code: 881122 Date and Time: November 22, 1988, 10:21 AM Target: Evergreen Trees O Frequency: 35 GHz -2 o 4" - -6 m -8 m 10 -- 4x — -62 L............................ 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Blue Spruce & Norway Spruce (Picea Puryens & Picea Abies) m 2 -Data Set Code: 881122 on ~Date and Time: November 22, 1988, 10:21 AM 0 O Target: Evergreen Trees c Frequency: 94 GHz. -2 o -4 = -6. -8 -12 O 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Blue Spruce & Norway Spruce (Picea Puryens & Picea Abies) 90

F., White Codar:Bushes White Cedar bush (Thuja ocidentalis) Data set code: 881116 Height: 3 mn Density: 80 % Average leaf (or needle) dimension:. $ cm Leaf moisture content: 56 % Percent vegetation cover: 30 0/ Pe~rcent cover of undergrowth: SO/o Description: dense stand of White cedar bushes 911

MMW DATA FOR TREE: C-,ANOPIES Close up view of branches of White Cedar bush 2 Data Set Code: 88t 1 16 X-/ 0 Date and Time: November 16, 1988, 11: 12 AM -2 TeTarget: Bushes C-~, Frequency: 35 GHz 0,-4 0~~~~~~~~~~,. i."':,:-8..........~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~......................... X~~Dt St Goe 881116ir++X - 0 - Date and Tme: Novemert 16 1988-| 1 eg1:1 Targte Beauashesal Gren Tu~ ~ena -i4 0 -t8 4) 1 0 W -12 414 "~-12 4 -18 6 08 i 0 ~20 30 40 50 6 incidence Angle (degrees) White Cedar at Botanical Gardens (Thuja Occidentalis) White k".1e-dar at2

MMW DATA FOR TREE CANOPIES 2cI ~, I., I''' I'''. I "'''. I''''' I'' ~'' I I ~ Data Set Code: 881116 tomt ~ I Date and Time: November 16, 1988, 11:12 AM Target: Bushes -', Frequency: 94 GHz.0.Z -2 -4 -6.a~ 4 -1 - W { -8 CD HH —"x — I-H 1.!. a.. a..... I a ~ ~ 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) White Cedar at Botanical Gardens (Thuja Occidentalis) 4 W' W'' I I'' I I W W W W W i W W W W. W W' I W W W W W W W I' W',2 Data Set Code: 881116 CD Date and Time: November 16, 1988, 11:12 AM Target: Bushes - 0 Frequency: 140 GHz -2 O -4 -6 - -8 m -10 - -— m — H -lo,,~ HH -12......... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) White Cedar (Thuja Occidentalis) 93

VII. MMW DATA FOR GRASSES Grass Data set code: 871102 Description: cut grass with wet surface 10 Data Set Code: 871102 (grass) m Date and Time: November 2, 1987, 2:45 PM ~, 8 Target: Grass 6 s Frequency: 94 GHz _r 4 o 2 0 -2 c -4 ~.' -6 - W m -8 -10.....,,,, 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Grass Height = 10 cm 12..... 2....,...,.......... I......IF. 8 8 Data Set Code: 871116 — 3m Date and Time: November 16, 1987, 11:17 AM X 4 Target: Grass = 0^. Frequency: 35 GHz 0 -4 o -8 -12 C-16 6..,-V...... a.......................................... -20....... ) a.,...................o...... -24 + W' m -28 VH -32. 0 10 20 30 40 50 60 70 8C Incidence Angle (degrees) Cut grass at North Campus (Height = 5 cm) 94

871116 Data Set Code: 871116 m' 4 m Date and Time: November 16, 1987, 11:17 AM Target: Grass 2 Frequency: 94 GHz 0 o 0 - -2'.~ -4 o -6 o.. -t —- VV -8 -10.............................. 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Cut grass at North Campus (Height = 5 cm) 2 - Data Set Code: 880812,m Date and Time: August 12, 1988, 1:28 PM Target: Grass -2 Frequency: 94 GHz m -10 -6 0 -18 -............... 3........,1............... ~-12 -16 -20 30 40 50 60 70 80 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Cut Grass (Height = 6 cm) 95

Tall Grass (Amaranthus) Data set code: 881202 Grass Moisture Content: 37.6%/ Height: 50 cm Description: uncut.:...:......EEli......... w..'..I............ Amaranthus over chickweed l l as | —_~~~9

MMW DATA FOR GRASSES 881202 6 Data Set Code: 881202 Date and Time: December 2, 1988, 9:24 AM'o 2 Target: Ground Cover Frequency: 35 GHz 0 0 -2 4) - m -4?'".............................. -10 VV 0 -12........."....HV... -14 HH —-....................6.. -16 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Amaranthus over chick weed 8 Data Set Code: 881202 Date and Time: December 2, 1988, 9:24 AM 6. Target: Ground Cover 4 - Frequency: 94 GHz 0 -2 -4 = ~.............. -... - - - -,, )'" % "*.................. -8................. -12 v......... -14 -16 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Amaranthus over chick weed 97

881202 10 8 - Data Set Code: 881202 _'' Date and Time: December 2, 1988, 9:24 AM 6 Target: Ground Cover 4 Frequency: 140 GHz _*2 X -4............... 0 -2 ) -4 o -10.........o....... HV -14 10 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Amaranthus over chick weed 98

881103 Tall Grass (Andropogon gerardi) Data set code: 881103 Leaf Moisture Content = 33% Height: 80 cm Description: dry, uncut 2 - Data Set Code: 881103 C 0 - Date and Time: November 3, 1988, 9:58 AM -2 7 Target: Ground Cover > -4.. Frequency: 35 GHz C -4 -6 -8 o -10 -12 n 14 o ~"".~................. 1............................. -16............. - -18 -20... -22 -.........O....... VH -24 -26.......... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Data Set Code: 881103 CD' I Date and Time: November 3, 1988, 9:58 AM 0 Target: Ground Cover Frequency: 94 GHz -2 - -4- 0 -6 -= -8..... -810 ~ -12 -14 -16....... I....... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) 99

881108 Grass (Andropogon gerardi) Data set code: 881108 Leaf Moisture Content = 44.5% Height: 80 cm Description: moist, uncut 0 - Data Set Code: 881108 X- 2 Date and Time: November 8, 1988, 9:48 AM -2 Target: Ground Cover * -4 Frequency: 35 GHz -6 o -8 m -10 t -I1 D 12t ~ i*~ —w-e~~-a m 14 W -18 - - - - HH.20 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Turkey Foot or Big Bluestem (Andropogon gerardi) 100

881108 A 2 Data Set Code: 881108 Date and Time: November 8,1988, 9:48 AM Target: Ground Cover c - 0 Frequency: 94 GHz -2 o -4 o o -6 -8 Y -10 + w m -12 —. - HH -14 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Turkey Foot or Big Bluestem (Andropogon gerardi) Data Set Code: 881108 co 4 -~ L Date and Time: November 8, 1988, 9:48 AM ~ 2 Target: Ground Cover _* - t Frequency: 140 GHz 0 o. -10 -lo., I. 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Turkey Foot or Big Bluestem (Andropogon gerardi) 101

881027 Tall Grass (Bromus inermis) Data set code: 881027 Leaf Moisture Content = 70 % Height: 80 cm Description: uncut 0 ~Data Set Code: 881027 (GC)'o -2 Date and Time: October 27, 1988, 3:22 PM Target: Ground Cover C -4 Frequency: 35 GHz -6 -8 c 10. -12.. co -14 -16 0 W c0 2 Data Set Code: 881027 -20 6 - = W...................., -12 _ i m -18 0. -2I Fqn 94G 0-12~~~102 m~~~~~~~~~~0

8 81 1 14 Grass (Bromus inermis) Data set code:. 881114 teaf Water Content 43~1% Height: 10 cm Description: cut 7:x4.....:..... ~ A:...................................C....t........Broo grass.(Bro us.ine 0 3..............................................................~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~:......................................,:j:: ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~~~~~~~~~~ ~~~~~~i~~~~~~iiiiiiiiii~~~~~~~~~~~~~~~~~~~~~~~~~~~~i~~~~~~..........................~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~:~8~~..............~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~j:::::::;1~:1: ~~~~~~~~~~~~~~iP~~~~~~~~~l~ ~ ~ ~ ~ ~ ~~.............. x ii"xx" L 1"', Mwf`Am lficatons a................i Vi -:ijjjj~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~~~i ~r~~:~:::illi~::::~ x:,.i::: xl::::i.::::3: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~X:...... I~srr;w,, ~~l~f ~~s~l ri i~i~~~PF~i~~~Ui i~lis~i~* -i::::,:.: iiXZ Nii i~~~~~~~~i iil~~~~~~~~~~~~~~u Brm sinri

881114 Data Set Code: 881114 2 Date and Time: November 14, 1988, 11:19 AM CD Target: Ground Cover O 0 Frequency: 35 GHz -2 o -4 -6 0,L ~ ~ ~.a —~.................. -8..................................:*+z -8 * -10 8n I *..H....... O....... HV 0 =I,,iM - - -x- - HH -14.. 6 Data Set Code: 881114 Ot.m Date and Time: November 14, 1988, 11:19 AM P. 4 - Target: Ground Cover c 2 t Frequency: 94 GHz C 2 -6 ao -8 10 -0 VH o -12 0 1 0 20 30 40 50 60 70 80' -10.."....104 104

881114 10........, Data Set Code: 881114 8 Date and Time: November 14, 1988, 11:19 AM Target: Ground Cover 6 t Frequency: 140 GHz 4 o 2 0 0 0 a. a.... 0 -2 1.a3.~............ 13 I —---- +- W am -4................ VH mD -6 -8 -I 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Broom Grass (Bromus Inermis) 105

881115 Grass (Bromus inermis) Data set code: 881115 Leaf Water Content = 50% Height: 25 cm Description: uncut 0 - Data Set Code: 881115 X- Date and Time: November 15, 1988, 1:51 PM -2 - Target: Ground Cover c " Frequency: 35 GHz -4 -6 0 -10 m i.. H -16 0 1 0 20 30 40 50 60 70 80 Incidence Angle (degrees) Broom Grass (Bromus inermis) 106

881115 6 ~ ~ ~, ~ ~ ~, ~ I ~ I, ~ I ~ ~ i - I ~ ~, ~.. 4 Data Set Code: 881115 m'2 Date and Time: November 15, 1988, 1:51 PM Target: Ground Cover 0 Frequency: 94 GHz - -4 - o -6 -8................ -10 -12................................ -14 -20 a I I.aa. I 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Broom Grass (Bromus inermis) 6 w w w V......... -.........V -6 Data Set Code: 881115 m 2 Date and Time: November 15, 1988, 1:51 PM F -2~ Frequency: 140 GHz 0 e -85~. m-10' -12 -14 F w * -18'....'....'....'....'....'....'.... -20.... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Broom Grass (Bromus inermis) 107

88 1 1 7 Grass (Lythrurn salicaria) Data set code: $881117 Leaf Moisture Content 24,,8% Height: I m Description:. uncut -.. r. -k t.. I M........ Amp~~~~~~~~~~~~~~~~~~~~~~~... X.......... —......g| || BjB~~~~~~~~~~~~........-...... B0 -. -........ gZ l| Purple loose stfrife (Lythrum salicaria)..............10 8..

881117 20,.... I. I, I I'' Data Set Code: 881117 m 16 Date and Time: November 17, 1988, 9:54 AM 12 Target: Ground Cover 4_ Frequency: 35 GHz q.- 4 0 8 -24 Purple Loose Strife over water (Lythrum salicaria) ~0~... -8 -....-12.......................a.................. o -16........o....... H -20 HH Purple Loose Strife over water (Lythrum salicaria) c 8 Fnrequdency: 94 GHz A 16 -20 t C o -24 01 12 -8 -12 - 12.................... -16 la -2 -24 0 110 20 30 40 50 60 70 80 Incidence Angle (degrees) 109

890406 Grass Data set code: 890406 Leaf Moisture Content = 70 % Height: 4 cm Description: cut, packed down by winter's snow. This is the grass from under the Brighton snow for which data was taken in early 1989. 16.,. 14 12 Data Set Code: 890406 m 10 * Date and Time: April 6, 1989, 2:51 PM P.. 8 Target: Grass 6 Frequency: 35 GHz 4 2 0 -4 o -8 >t —W.......... - -10 i -20................ VH 0-12 -14 -22 -24' H -26 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Brighton grass substrate 110

890406 12 8 _ Data Set Code: 890406 _A' ~ Date and Time: April 6, 1989, 2:51 PM X!. 4 Target: Grass Frequency: 94 GHz * 0 -4 -8 -16 0 1 0 20 30 40 50 60 70 80 Incidence Angle (degrees) Brighton grass substrate Data Set Code: 890406 m 4~ Date and Time: April 6, 1989, 2:51 PM XI Target: Grass _ 0 Frequency: 140 GHz -12 T -@@@w —...s....................... H. -24 -1 -.,- - H 28 t......'..... IN 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Brighton grass substrate Date and Time April 6, 1989, 2:51 PM O -16 - -20 0 10 20 30 40 50 60 70 80

VIII. MMW DATA FOR ROAD SURFACES A. Asphalt Asphalt Data set code: 860918 Surface RMS height: 0.7 mm Description: smooth, dry asphalt 860918 20 16 Data Set Code: 860918 1m2C Date and Time: September 18, 1986, 12:40 PM 12 Target: Asphalt e 80 Frequency: 35 GHz 8 O m1 -- " I- H' - -8 -20 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Dry Asphalt at Willow Run 112

Asphalt Data set code: 871113 Surface RMS height: 0.42 mm Condition: dry, smooth asphalt 32'. 28 Data Set Code: 871113 24 Date and Time: November 13, 1987, 1:00 PM n 20 j Target: Asphalt 16 Frequency: 35 GHz * 12 - 8 4 0 *' -8. 12 0.. ~ -1 *............ -20 W..... -241 o............... VH -28......... -32,,,. 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) 10.... I....,..... I. 8. Data Set Code: 880928 m 6 - Date: September 28, 1988 4 Target: Asphalt e 2 Frequency: 94 GHz -2 0 14 -6 ~". -8 -10 13......... -12.-14................ \VH.. -18.. -20 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) 113

Asphalt Data set code: 880923(1) Surface RMS height: 0.42 mm Condition: smooth, damp asphalt 10 8 Data Set Code: 880923(1) I 46E Date: September 23, 1988 ". 4 2 Target: Asphalt _ 2 L Frequency: 94 GHz -2 0 o -6 -8 -12.......'....................... ": -81 t*..........0..... o -14 0 -16.........H....... V m -18 -20 -22..... 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Damp Asphalt at Dow Parking Lot 880923(2) 12 10 Data Set Code: 880923 Date: September 23, 1988 S,6 Target: Asphalt 4. Frequency: 94 GHz *0 2 yU.. 0 m -2 - o -4 cM -6 -20 ~~~~~,..,,, -,. -8 0 0,.-1 8.........................114 ap-16 t — K- HH% -x,. -12 el~ ~ ~ ~ ~~Iniec.nl dges "~ ~ ~ Dr'shl............1~,. ~' ~ -14........o......

Rough Asphalt Data set code: 881109 Surface RMS height:, 2 mm Conditiont rough, dry asphalt Asphalt at Botanical Gardens 1i5 1E~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.............................__-I........ YYY~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~.............YY........................ |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~...................................... |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~........................................... N S, R I I 1 R 1 0 i i fl S S ___i~~~~~~~~~~~.............................................. ad

881109 36............... I...'. 32 Data Set Code: 881109 Date and Time: November 9, 1988, 10:17 AM 28 ej Target: Asphalt 24 Frequency: 35 GHz 20 NOTE: Overall calibration uncertain -- values are relative only! 3r 16 0 12 ~ 0 a. n -16 "'"................ 0.............0 20 30 40 50 60 70 80....... Rough Asphalt at Botanical Gardens -4 8 W 1................... -8 - Target: AsphaltV... -12 -6 — _ - - FH -16 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Rough Asphalt at Botanical Gardens 22 Data Set Code: 88 1109 20 - Date and Time: November 9, 1988, 10'17 AM 18. Target: Asphalt 16 - Frequency: 140 GHz 14 NOTE: Overall calibration uncertain -- values are relative only! Q) 2.........~~.............13-...... 0' W.a................... -2 -4 -6 -. H -8 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) tt6

871 1 1 3/88081 5 B. Gravel Gravel Data set code: 871113 and 880815 Surface RMS height: ~ 2 mm Typical stone size: - 6 mm Description: dry gravel Gravel in North Campus parking lot 1.7

871113 Data Set Code: 871113 _ 4 4 Date and Time: November 13, 1987, 3:14 PM X. r Target: Gravel c ~ Frequency: 35 GHz -4 -8 0 -12. 3....................o 1....................' *-16 -20.~ r W mo -24 _................ VH -28...,,,,,, I. 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Gravel in North Campus Parking Lot 88081 5(2) 14..I......I..... I.... I..... 14 12 Data Set Code: 880815(2) 10 Date and Time: August 15, 1988, 2:15 PM XP, 8 Target: Gravel 6 2 Frequency: 94 GHz 4 o 2 o -2 _H -4 I. C -6..- -10..................... x, -12 ~ (3-14....... 3 m..........'13'0....... VH m -16 -18 -20.. 0 10 20 30 40 50 60 70 80 Incidence Angle (degrees) Gravel in North Campus Parking Lot 118

APPENDIX A A Millimeterwave Network Analyzer Based Scatterometer Fawwaz T. Ulaby Thomas F. Haddock Jack R. East Michael W. Whitt Reprinted from IEEE TRANSAC'TIONS ON (GEOS'IEN( E AND REMOTE SI:ENSIN(; Vol. (;E-26, No. I, January 1988 A-l

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 26, NO. I, JANUARY 1988 75 A Millimeterwave Network Analyzer Based Scatterometer FAWWAZ T. ULABY, FELLOW, IEEE, THOMAS F. HADDOCK, MEMBER, IEEE, JACK R. EAST, MEMBER, IEEE, AND MICHAEL W. WHITT, STUDENT MEMBER, IEEE Abstract-The Millimeterwave Polarimeter (MMP) is a network- RR ECEIVR TRPANSMITTER analyzer based scatterometer and reflectometer system that has been ELECTROMCS HOUSE developed in support of a program to characterize radar clutter at 35, CONTAJNS NETWORK ANALYZER SYSTEM AND COMPUTER FOR CONTROL 94, and 140 GHz. A HP 8510A network analyzer is employed in the A NDATA STORAGE car MMP system as a signal conditioner and processor to facilitate realtime data reduction, to reduce the short time-delay leakage noise inherent in traditional FM/CW radar, and to further enhance the signal-to-noise ratio of the system through signal processing techniques. // Cr ATC Operation of the system at millimeter wavelengths is achieved with up- - 110 VAC TARTI conversion and harmonic downconversion. The use of harmonic down- \ converters permits low-frequency signal connections between compo-1 1 - nents of the system and allows easy reconfiguration in either aACKSCATTER MODE scatterometer, bistatic, or reflection/transmission modes. RECEIVER ADJUSTABLE I. INTRODUCTION MOUT NETWORK ANALYZER THE PRIMARY design objectives of the Millimeter- sTGTEM wave Polarimeter (MMP) is to achieve a system that can operate at 35, 94, and 140 GHz with full polarization o' —' and phase capability. It should operate from a truck plat- TRANSMITTER form as a scatterometer for backscatter measurements and* in the laboratory for bistatic and transmission measure- ISTATIC MODE ments, and should have ranging and real-time processing capabilities. The HP 8510A is an automatic vector net- NETWOK ANALYZER SAMPLE work analyzer with a computer-control system that allows sYE TRANSMRER CE vector error correction of imperfections through the use [{lif il of calibration standards. It provides the needed flexibility and signal conditioning and processing for our requirements. 0 The three configurations of the MMP are illustrated in REm.ECnON /TRANSMISSION MODE Fig. I. Fig. I(a) illustrates the 94-GHz system in its back- Fig. I. The three operating configurations ot the MMP. scatter mode. In this configuration it operates from a variable-angle mount on the end of an extendable boom configuration the two subsystems directly face one anmounted on a truck. The front end RF and IF components other, so the transmitted signal passes directly through the are mounted on the boom top, while the network analyzer sample. and ancillary data processing and recording equipment are Note that in the bistatic and reflection/transmission mounted in a control house on the bed of the truck. Fig. modes the receiver and transmitter sections must be po1(b) shows the bistatic measurement configuration in sitioned independently of each other. Scatterometer usage which the transmitter and receiver sections are separated requires that the entire system be portable, with the front from one another and used to make bistatic measure- end moving remotely and independently from the HP ments. Fig. I(c) illustrates the transmitter and receiver 8510A back end. The MMP system illustrated in Fig. 2 subsystems, operating without the lens-horn antennas, to addresses each of these goals, while providing standard make transmission and reflection measurements. In this operating procedures and data format for all three types of data acquisition. Manuscnpt received January 12. 1987; revised July 30. 1987. The authors are with the Radiation Laboratory. Department of Electrical II. MMP DESIGN Engineenring and Computer Science. The University of Michigan. Ann Ar- The design goal was to produce a single versatile inbor, MI 48109-2122. The design goal was to produce a single versatile inIEEE Log Number 8717530. strument with the ability to be configured in the three de0196-2892/88/0 100-0075$0 1.00 c 1988 IEEE A-2

76 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 26. NO 1. JANUARY 1988 93 TO 95 GHz 2TO 4 GHz POLAR ZER i art 0 (0 (i) TRANSMI T HORN BP RARMOMC ANTENNA NETWORK ANALYZER TER ER SYSTEM co 91 10.11 HP 8350B TRANSMITER SWEEPER.. iC O al DIELECTRIC I HP 8511A V POLARIZATION m FREQUENH b1A H POLARIZATION I.-( b2 d I'E 1 RECEIVER co IF TEST SET u by aNERCNNECT.... is d 2TO4 GHz HP 8510A REeCE NED - T NETWORK S=NALS ECVE ANALYZER HORN HARMCNIC (a) -2TO4 GWz HP 83508 S S ration) thoughows a leshr antnn tothmX-BAND by Snoak e reflectin win te AEQUBCY H POLARIZATION eeer 2TO4 C..d' 1 RE IF TESTSErD SIGNALS HP 9000 SERIES bthHP81AtoasHPtu signal ( r. Thi po ar itlmow

ULABY et al: MILLIMETER-WAVENETWORK ANALYZER-BASED SCATTEROMETER 77 COPOL CROSSPOL Contour Map of Contour Map of Contours are in units of Contours are in Units of POWER (dB) POWER (dB) Peak Power is 3.929 Peak Power is 0.001 -2.5.... -2.5 Azimuth (Deg) 2. -2.5 Azimuth (Deg) 2.5 Minimum: -40; Maximum: 0; Contour interval: 3. Fig. 3. Like- and cross-polarization traces for a typical MMP antenna. noise floor of the system. The HP 8510A has error cor- TABLE I rection routines that correct for imperfections in the test TRUCK MOUNTED SCATTEROMETER PARAMETERS circuitry through measurements of standard calibrators. Fry: 35 9 10 GH By using an HP 85 10A as a radar back-end, sources of RW,,,V,. Oto2.0GHz system measurement error can be characterized and par- S 1 msirq. 51. 101, 201. 401 reqisw p tially subtracted from the signal, hence, greatly increas-, ing system sensitivity over that provided by a conven- In0AIr,: to 70 todegr.o tional design. PlnM HegI: 3 meen mirnum. to 18 mets maximum In addition, since the HP 8510A makes measurements No EequW a: 35 GH: -36d8 by determining the phase and amplitude of returned sig- 94Ghz: 34dB nals over a series of stepped frequencies, all phase infor- 140GHz: 37d8d mation is retained. When both horizontal and vertical (Tl." v.s or h-O met.ers ando -50 d..r..s the actual h st m vary mh modes of polarization are measured, complete polariza- nw tion information can be obtained. This allows the recon94 GH.: 3,71, struction of any mode of polarization, linear or circular, 94GHz 31m thus making the system completely polarization agile. 1 40GHz 1 38 m This capacity can be used to completely specify the scat- G 000 to419sqm 94 GHz: 0002 to 4 78 sq., tering matrix of an object or target of interest. The HP 8510A has the capability to perform complex:inary math operations on pairs of swept signals. For eximple, a signal may be memorized and used to operate on ~ PBoes: *rVeO VeRs rno. (AR.cC/IM;ubsequent signals to remove or reduce unwanted re- rd po v y (i R;ponses. This can be used to reduce reflection and leakageh frn ioise from within the system, as well as to reduce unvanted responses from outside the instrument. as well as to measure the backscattered power as a funcThe HP 8510A can perform real-time fast-Fourier tion of range. In studying the scattering from vegetation ransforms from the frequency domain, in which the data canopies, for example, it is possible to record the differs taken. to the time domain. Range-gating capabilities in ential scattering as a function of range from the top of the he time domain allow setting the response of the instru- canopy down to the underlying ground surface. lent to a specified time range. This can be used to reject Table I lists projected system performance specificaignals reflected from targets outside of the desired range, tions, based on laboratory tests and specifications of our A-4

78 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 26. NO 1. JANUARY 1988 2 TO 4 GHz TRANSMITTED SWEPT SWEPT RF SIGNAL HP 8350B SI-NAL TRANSMITTER o SWEEPER ino3 EFEsE X-BAND LO co HP 8511A V POLARIZATION SIGNo;_ WeNFEFRKXta H POLARIZATION b2 F 5. *R c RECEIVED SWEPT 03 a2 RF SIGNAL co | |-tIF TEST SET a. I NERCONNECT \ HP 9000 SERIES NRETWORK RE ANALYZER SIGNALS D RIVE PRINTER Fig. 4. Bistatic configuration of the system. 2 TO 4 GHz WAVEGUIDE SWEPT SIENT RV. HP 8350B ITRANSMITTER R T ECEER SAMPLE _ n Nrns a poral resolution and can be used to reduce and study theIGNAL effects of fading. C. Transmission Mode LL* HP 8511A bU ~' PIFNTESTSET Fig. 5. Reflection/transmission configuration of the system. equipment. The values for the noise-equivalent a' for the only here the transmitter and receiver sections move in94- and 140-GHz systems were derived on the basis of dependently of each other in making the measurements at tests in the laboratory. various angles. Ease of movement of the two subsystems The bandwidth of the MMP can range from 0 to 2 GHz, comes from the low-frequency IF (2 to 4 GHz) and LO and can be changed in real-time. Narrow bandwidth al- (X-band) interconnections. Note that due to range-gating, lows the system to have high spectral resolution, and bistatic measurements can take place anywhere, in the hence have good determination of frequency-dependent field, where the numerous unwanted reflections can be features of the targets. Wide bandwidth allows good tem- time-gated out, or in the usual anechoic chamber setting. poral resolution and can be used to reduce and study the Antenna patterns of a typical MMP antenna are given The transmission configuration diagram is shown in polarization isolation is better than 40 dB. now the lens-horn antennas are removed and samples are B. figuration the polarization switch is used to select either a,-5

ULABY et al.: MILLIMETER-WAVENETWORK ANALYZER-BASED SCATTEROMETER 79 RETURN FROM TREE CANOPY VS. RANGE W FOR TOTAL CANOPY oo = - 9.58 dB 0.. 10100 -5. r W 0 I ~ i0: IU. O -20. 10 1,0 -10. i Fo or ~ 0- 3. -250. - 0. 10. 1020. 30.. 50. TIDEREES FR(M NADIRs) Fig. 6 shows a histogram6. Histogram of time-domain response incidence angle for a leaf of cross section of approxiGHz. The target was a dense stand of trees, and the data data was taken in an anechoic chamber at 35 GHz with - -. A-6 _~. i,t I, I of the system operating in the scatterometer mode at 35 mately 40 cm2, with 63-percent moisture content. This GHz. The target was a dense stand of trees, and the data data was taken in an anechoic chamber at 35 GHz with was taken with a full bandwidth of 2 GHz at an angle of the system operating in the backscatter mode. approximately 45 degrees. Calibration was performed A-6

80 IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING, VOL. 26, NO. I. JANUARY 1988 35 GHz, VV POLARIZATION -10 7.s CM LEAF ROTATES ABOUT STEM AXIS -20 -, -30' z o -50 -6 634% MOISTURE CONTENrT LEAF AREA APPROXIMATELY 40 CM2 -70 - -9C -60 -30 0 30 60 90 ANGLE (DEG.) Fig. 8. Leaf backscatter cross section versus angle at 35 GHz for a leaf with 63.4-percent moisture content. bandwidth, polarization, and configuration of the MMP Remote Sensing: Active and Passive (Reading, MA: Addison-Wesley). In allow for a flexible system for field as well as laboratory addition, he is coeditor of the Manual of Remote Sensing, 2:,d ed., vol. I, American Society of Photogrammetry. use. Dr. Ulaby is a member of Eta Kappa Nu, Tau Beta Pi, and Sigma Xi. He has been named the Executive Editor for IEEE TRANSACTIONS ON GEOREFERENCES SCIENCE AND REMOTE SENSING, 1984-1985, and was the Geoscience and Remote Sensing Society's Distinguished Lecturer for 1987. He was named [1] W. K. Saunders, "CW and FM radar systems," in Radar Handbook, an IEEE Fellow in 1980 "for contributions to the application of radar to M. I. Skolnik, Ed. New York: McGraw-Hill, 1970. remote sensing for agriculture and hydrology," received the GRS Society's [21 M. I. Skolnik, Introduction to Radar Systems. New York: McGraw- Outstanding Service Award in 1982, and its Distinguished Service Award Hill, 1962. in 1983. In 1984, he also received a Presidential Citation for Meritorious [31 F. T. Ulaby, R. K. Moore, and A. K. Fung, Microwave Remote Sens- service from the American Service of Photogrammetry. He received the ing: Active and Passive, vol. I. Reading, MA: Addison-Wesley, University of Kansas Chancellor's Award for Excellence in Teaching in 1981. 1980, the University of Kansas Gould Award for "distinguished service to higher education" in 1973, and the Eta Kappa Nu MacDonald Award as I* an "outstanding electrical engineering professor in the United States of America" in 1975. Fawwaz T. Ulaby (M'68-SM'74-F'80) was born in Damascus, Syria, on February 4, 1943. He received the B.S. degree in physics from the Amer- Thomas F. Haddock (M'86) was born in Washican University of Beirut, Lebanon, in 1964 and ington, DC, on November 2, 1949. He received the M.S.E.E. and Ph.D. degrees in electrical en- the B.A. degree in mathematics and the M.S. and gineering from the University of Texas, Austin, Ph.D. degrees in physics from the University of in 1966 and 1968, respectively. Michigan, Ann Arbor, in 1972, 1977, and 1984, From 1968 to 1984, he was with the Electrical respectively. Engineering Department at the University of Kan- From 1984 to 1985 he was Manager of Develsas, Lawrence, where he was the J. L. Constant opment Projects at Applied Intelligent Systems, a Distinguished Professor, and the University of machine vision firm involved in real-time optical, Kansas Center for Research, where he was Director of the Remote Sensing infrared, and X-ray vision systems. He is curLaboratory. He is currently with the Radiation Laboratory and the Depart- rently with the Radiation Laboratory and the Dement of Electrical and Computer Engineering, University of Michigan, Ann partment of Electrical Engineering and Computer Science, University of Arbor. His current research interests involve microwave propagation and Michigan. He has conducted research in the fast flux density vanations of active and passive microwave remote sensing. Along with R. K. Moore quasi-stellar objects at a wavelength of 12.5 mm. Other research has inand A. K. Fung, he is a coauthor of the three-volume series Microwave cluded development of real-time alphanumeric character recognition algoA-7

ULABY et ai. MILLIMETER-WAVENETWORK ANALYZER-BASED SC \TTEROMETER 81 rithms and ultrasonic weld inspection algorithms. Prior to receiving the Michael W. Whitt (S'83 was bom in St Charles, Ph.D. degree, he worked as Applications Engineer for Sarns/3M, a man- MO, on December 3, 1962. He received the B S. ufacturer of heart-lung machines and cardiac assist devices, where he de- degree in electrical engineering from the Univerveloped electrodes for manufacturing applications. Current research inter- sity of Arkansas, Fayetteville, in 1985 and the ests are millimeter-wave scattering and emission from natural targets. M.S. degree in electrical engineering from the Dr. Haddock is a member of the American Astronomical Society. University of Michigan, Ann Arbor, in 1986. Since September 1985, he has been a Graduate ~'* Research Assistant at the University of Michigan Jack R. East (S'70-M'72) received the B.S.E., M.S., and Ph.D. degrees Radiation Laboratory, where he is currently workfrom the University of Michigan, Ann Arbor. ing toward the Ph.D. degree. He is now an Associate Research Scientist in the Solid-State Electronics His research interests include millimeter-wave Laboratory of the University of Michigan, working in the area of micro- radar, radar polarimetry, and polarimetric scattering from terrain and vegwave- and millimeter-wave solid-state devices. etation canopies. A-8

APPENDIX B: RELEVANT PUBLICATIONS [1] F.T. Ulaby, T.F. Haddock, J.R. East AND M.W. Whitt. A Millimeterwave Network Analyzer based Scatterometer. IEEE Transactions on Geoscience and Remote Sensing, Vol. 26(1). Jan.1988. [2] M.W. Whitt and F.T. Ulaby. Millimeter-Wave Polarimetric Measurements of Artificial and Natural Targets. IEEE Transactions on Geoscience and Remote Sensing, Vol. 26(5). Sept. 1988. [3] T.F. Haddock and F.T. Ulaby. 140-GHz Scatterometer System and Measurements of Terrain. Submitted for publication in IEEE Transactions on Geoscience and Remote Sensing. [4] M.W. Whitt and F.T. Ulaby. Millimeter-wave Polarimetric Measurements of Artificial and Natural Targets. Proceedings of IGARSS'87 Symposium, Ann Arbor, May 1987. [5] F.T. Ulaby, T.F. Haddock and R.T. Austin. Fluctuation Statistics of Millimeter-Wave Scattering from Distributed Targets. IEEE Transactions on Geoscience and Remote Sensing, Vol. 26(3), May 1988. [6] M.T. Hallikainen, F.T. Ulaby and T.E. Van Deventer. Extinction Behavior of Dry Snow in the 18- to 90- GHz Range. IEEE Transactions on Geoscience and Remote Sensing, Vol. GE-25(6). Nov.1987. [7] M.T. Hallikainen, F.T. Ulaby and T.E. Van Deventer. Extinction Coefficient of Dry Snow at Microwave and Millimeterwave Frequencies. Proceedings of IGARSS'87 Symposium, Ann Arbor. May 1987. [8] T.E. Van Deventer, 7.R. East and F.T. Ulaby. Millimeter Transmission Properties of Foliage. Proceedings of IGARSS'87, Ann Arbor. May 1987. [9] F.T. Ulaby, T.E. Van Deventer. J.R. East. T.F. Haddock and M.E. Coluzzi. Millimeter-wave Bistatic Scattering From Ground and Vegetation Targets. IEEE Transactions on Geoscience and Remote Sensing, Vol. 26(3). May 1988. B-1

[10] F.T. Ulaby, T.F. Haddock and M.E. Coluzzi. Millimeter-wave Bistatic Radar Measurements of Sand and Gravel. Proceedings of IGARSS'87 Symposium, Ann Arbor. May 1987. [11] K. Sarabandi, F.T. Ulaby, and T.B.A. Senior. Millimeter Wave Scattering Model for a Leaf. Accepted for publication in Radio Science. [12] F.T. Ulaby, T.H. Haddock and Y. Kuga. Measurement and Modeling of Millimeter-wave Scattering from Tree Foliage. Accepted for publication in Radio Science. [13] Y. Kuga, R.T. Austin, T.F. Haddock and F.T. Ulaby. Millimeterwave Radar Scattering from Snow Part I —Radiative Transfer Model wvith Quasi-Crystalline Approximation. To be submitted for publication in IEEE Transactions on Geoscience and Remote Sensing. B-2