1、18 4 b+rVol. 18No. 41 99 6 MJOURNAL OF GLACIOLOGY AND GEOCRYOLOGY 1 99 6? uSAR m李 震 曾群柱 孙文新(S S b+r , 730000)K1s d r(SAR) # +$ , t?fq r(SIR- C) |? Co aSAR ,4 |Lb YV) a “ m9 a .a ) , BAYESSs ZE 3 us mb LTV , o aSARm Vb1oM d r 1 “d “1 b H, , E 1 p # bWM f ,y7 S K1pb */ |V 1“ Vn;a#$o 5bo. ?,i |V,o. , d
2、 r(SAR) sO q,#o* ? ?as,i#sO q b*K/ Bb d r 4 |80 MX(Matzler et al., 1984)b “Ho a0/ # r/ ?Z, SAR Nb(Rott et al.,1991; Shi et al., 1994 )b M ,a qSAR 4 |4 4, PYVs1 ?s a4 |bKDZEb St bt? (NASA)1994 M410t?f q r(SIR- C), | a q(CaLaX BAND, HHaVVaHVaVH)SAR b Qf |Co SAR ,? umb2ZE o* o oMT(V a8 ).l+ | , MY “S +
3、bo*5 ?L? |,r “S1996 M114 l; SE1 S( |49471058)a*SE L i 7b#? b+4 k_ “b$ , s?L l 1+Z_ |bo. SAR rZ(Ulaby et al., 1982):P- r= K2(4P)3sPtG2R0R4 dA (1)T: Pr s q; Pt? q; R r “SW ; s r ; G “SZ_ r?L9m; R0 “S “ ; K robV d r. Z T(1) V A,Yo|y “S8 r“d Z b7 Z sY “S8Ya aoaZ T %bUlaby et al. (1982), A c 9F79F, 1 s M
4、 ebY7,V Y_ “ Yv,7 A“ AY(m1)bm1V YR0Y(Ulaby et al., 1982)Fig. 1The response of roughness of the snow surface to back- scattering coefficient M , Shi et al. (1992)N B, c ,l H,o e;v H,58 ebY vac v7, eb8 H, A “ M1; H, A “ M1b4 | VYV aY “S uY,sSbi O V B T# L ,Qb b34 |3. 1 u L u4S? pr, 8818 E, 4345 Nb u 3
5、674 :? uSAR m Mb+, b+ L17a/h bV 4 u4, b bSIR- C1994 M Qf | uSARa b 1.25GHZ (L BAND)a5.3 GHZ (C BAND) q, HHaVVaHVaVH Z T, sO qZ_8.4m, _6.2 mb CoZ Tm Lb H, | H u TMT1 b3. 2 ) #s L, SIR- CSAR4 |,mb 1) V /+Z (m2)bm2SAR ) s mFig. 2The diagram of SAR data processing andclassification(1) r_ “ mSIR- C 3SAR
6、JPL/STOKES M Ti(Ulaby et al.,1990):M- =M- 11M- 12M-13M- 14M- 21M- 22M-23M- 24M- 31M- 32M-33M- 34M- 41M- 42M-43M- 44M- 11 = 14S-hhS-*hh + S-vvS-*vv + 2S-hvS-*hvM- 12 = 14S-hhS-*hh - S-vvS-*vvM- 13 = 12ReS-hhS-*hv + 12 ReS-hvS-*vvM- 14 = - 12 ImS-hhS-*hv - 12 ImS-hvS-*vvM- 22 = 14S-hhS-*hh + S-vvS-*vv
7、 + 2S-hvS-*hv368b+r18 M- 23 = 12ReS-hhS-*hv - 12 ReS-hvS-*vvM- 24 = - 12 ImS-hhS-*hv + 12 ImS-hvS-*vvM- 33 = 12S-hhS-*hv + 12ReS-hvS-*vvM- 34 = - 12 ImS-hhS-*hvM- 44 = 12S-hvS-*hv - 12 ReS-hhS-*vv7Mueller M:M= SQdM- Q (2):S=1 0 0 00 1 0 00 0 - 1 00 0 0 - 1Q=1 0 0 00 1 0 00 0 - 1 00 0 0 - 1 T(2),|STO
8、KES Mueller , T(3)sY9 oZ T_ “ mbR0vvR0vhR0hvR0hh= 4PcosHosM11M12M21M22(3)T: os4Z_b(2) . u Y r7 3. 2 s| 3 Y,SARm) n51 . 2) bZE roa ( roa f ro#m roZEb LrT1 , |99 ( ro,rT A b H, L u u, v P M EsA,_ “ 1,B “S 7/_ “ YbY, “ T:R0 (Hi) = R0nf (Hi) (4)T: R0n “S + e ;7f (Hi)5 e b_3694 :? uSAR m “ ?B) , “ Y, ? s
9、 b T:f (Hi) = cos (Hi)f ( Hi) = cos2 (Hi)-Y H a,$mrT z,7 L= “ X b LV1 , f (Hi) = cos1.8 (Hi)b T(4) V,?BA B) L= , 9 T(Dozier et al., 1990):cosHs= cosScosH0+ sinSsinH0cos (T- A) (5)T: Hs L= ; S ; H0. ; A _; TfZ_Zb TaH0f“ 4, SaA5 u 3 (DEM),V ) ,DEM 3 L u a _mb T(5) p L= , T(4)SARm BB) , 3 “ mb(3)s Z Tm
10、 , BsY %) by Ya a u$ , mBAYESSs , 3s m(v 1)bv 1Co HHs TPhoto 1The snow- cover classificationresulted from C band HH image3. 3T#S|s m TMms 1 , Ys T(V1)b370b+r18 TV , Co HHaVV ?z us Ad u, 86%j95%W, uY 4, 8s 51%b ? z| s 7byN,8 ? s ,rm “bV1Co Z TSARms Table 1The accuracies of snow cover classification b
11、y C polarizatedSAR imagesY ( % )Z THH VV HV VH9895.251.790.751.387.468.287.769.3DEM , P uYrb# ZE a u,7 O um9 rb 6,y ,9 V “S sb u, ZE mb4 d r ?+4 /m#V4 | V?, H x b ERS- 1 JERS- 1sYzCo Lo SAR. , SAR Avv9 b 4 | H,C f , “ - Vn;# % YE,|NT Hq/m|A Vn;. b H, SAR Q ( AaYa )T “ -b*K 5B,/B T, |Z kb:T SFv yp V,
12、b IDDozier J and J Frew. 1990. Rapid calculation of terrain parameters for radiation from digital elevation data. IEEE,Transactions on Geoscience andRemote Sensing, 28 (5): 963j969.Matz ler C and E Schanda. 1984. Snow mapping with active microwave sensors.Int. J. Remote Sening, 5 (2): 211j218.Rott H
13、 and RE Davis. 1991. Multifrequency andpolarization SAR observationsonalpin glacier. Annals of Glaciology, 17: 66j71.Shi J and J Dozier. 1992. Radar back- scattering response to wet snow. Proceed-ings IGARSS 92 (2): 927j929.Shi J et al. 1994. Snow mapping in alpine regions with synthetic aperturerad
14、ar.IIEEE, Transactions on Geoscience and Remote Sensing, 32 (1): 152j158.Ulab y F T et al. 1982. Microwave remote Sensing, Vol. 2, Radar remote sensingand surface scattering and emission theory. Addison- Wesley pubbishingcompany.Ulab y F T and C Elachi. 1990. Radar polarimetry for geosciece applicat
15、ion.Artech House, Inc.3714 :? uSAR mA Study of Snow- cover Mapping with SARImage in the Tianshan MountainsLiZhen, Zeng Qunzhu and Sun Wenxin(Lanzhou Institute of Glaciology and Geocryology, Chinese Academy of Sciences, 730000)AbstractAccording of the imaging principle of Synthetic Aperture Radar and
16、 back- scatter-ing characteristics of snow, authors examined the capability of snow - cover mappingwith multifrequency and multipolarized SAR images from SIR- C carried by shuttle.The snow - cover can be mapped after a serial image proceeding on SAR data in theTianshanMountains. Theresult showsthat
17、C- bandHH andVV images can be usedtodiscriminate between wet- snow and snow- free area, and cross - polarized SAR im-ages of C- band can be used to discriminate between dry- snow and bare ground. Sothe SAR data can be used to map snow- cover.Key word: synthetic aperture radar, back- scattering, snow- coverBTe: , 3, 29 , 1988 M8q S/v *, “ -S S b+r p VbC1V Yb*aGISa d rm) #Tb372b+r18
