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Editor: Steven C. Reising Cumulative Issue #118 March 2001 ISSN 0161-7869 See page 3 for a description of images.
Editor: Steven C. Reising
Cumulative Issue #118 March 2001 ISSN 0161-7869
See page 3 for a description of images.
2 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
IEEE GRS-S AdCom, Officers and CommitteeChairs - 2001 GRS-29 (Division IX)PresidentWerner Wiesbeck
Executive Vice PresidentCharles A. Luther
Vice President forTechnical ActivitiesA. J. Gasiewski
Vice President forMeetings and SymposiaKaren M. St. Germain
Vice President forOperations and Financeand Director of FinanceJames A. Gatlin
Vice President forProfessional ActivitiesMelba M. Crawford
SecretaryThomas J. Jackson
AwardsKamal Sarabandi
Chapter ActivitiesAlberto Moreira
Conference CoordinationKaren M. St. Germain
Constitution and BylawsCharles A. Luther
Education DirectorDavid Weissman
Fellow EvaluationAndrew J. Blanchard
Fellow SearchKiyo Tomiyasu
MembershipAlberto Moreira
Newsletter EditorSteven C. Reising
NominationsMartti Hallikainen
Standards and MetricA. J. Gasiewski
Strategic PlanningAndrew J. Blanchard
Technical ActivitiesA. J. Gasiewski
Transactions EditorLeung Tsang
IGARSS 2000Andrew J. BlanchardDavid G. Goodenough
IGARSS 2001Anthony K. Milne
IGARSS 2002Ellsworth LeDrew
IGARSS 2003Didier Massonnet
IGARSS 2004Verne Kaupp
IGARSS 2005Wooil M. Moon
IGARSS 2006V. ChandrasekarA. J. Gasiewski
PACEJohn A. Reagan
Society on SocialImplications ofTechnologyKeith Raney
2001 AdCom MembersAndrew J. BlanchardA. J. GasiewskiThomas J. JacksonNahid KhazenieCharles A. Luther
2002 AdCom MembersJon A. BenediktssonMelba M. CrawfordDavid G. GoodenoughKaren M. St. GermainDavid Weissman
2003 AdCom MembersWilliam EmeryMartti HallikainenVerne KauppKamal SarabandiWerner Wiesbeck
Honorary Life MembersKeith R. CarverKiyo TomiyasuFawwaz T. Ulaby
Ex Officio With Vote:Nahid Khazenie (SeniorPast President)
Table of ContentsIEEE GRS-S AdCom, Officersand Committee Chairs . . . . . . . . . 2
Editor’s Comments . . . . . . . . . . . 3
President’s Message . . . . . . . . . . 3
Editorial Board Members . . . . . . . 4
AdCom Members . . . . . . . . . . . . 5
INDUSTRIAL PROFILEGAMMA Remote Sensing AG . . . 6
GRS-S Members Elected to the Gradeof Fellow, January 1, 2001 . . . . . 9
Introducing New GRS-S AdComMembers for 2001 . . . . . . . . . . 10
FEATURE ARTICLEESA's Second Earth ExplorerOpportunity Mission . . . . . . . . . 11
Call for Nominations for the GRS-SAdCom . . . . . . . . . . . . . . . . . . 14
GRS-S Expands Team to MeetChanging Needs of Society . . . . 15
First Int'l Microwave RadiometerCalibration Workshop . . . . . . . . 15
UpcomingConferences . . . . . . . . . back cover
Newsletter Input and DeadlinesThe following is the schedule for the GRS-S Newsletter. If you would like to con-
tribute an article, please submit your input according to this schedule. Input is pre-ferred in Microsoft Word, WordPerfect or ASCII for IBM format (please send diskand hard copy) as IEEE now uses electronic publishing. Other word processing for-mats, including those for Macintosh, are also acceptable, however, please be sure toidentify the format on the disk and include the hard copy.
GRS-S Newsletter ScheduleMonth June Sept Dec MarchInput April 15 July 15 Oct 15 Jan 15
Notice ToPotential AdvertisersThe IEEE GRS-S Newsletter publishes paid ad-vertisements for job openings, short courses,products, and services which are of interest tothe GRS-S membership. The rates for advertise-ments published in the Newsletter are:
PerSize Dimensions InsertionFull page 7" x 10" $400.00Half page $300.00Vertical 3.375" x 10"Horizontal 7" x 4.875"
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Ms. Susan SchneidermanBusiness Development ManagerIEEE Magazines/Newsletters445 Hoes LanePiscataway, NJ 08855-1331Tel: +1 732 562 3946Fax: +1 732 981 1855
Postal Information and Copyright NoticeIEEE Geoscience and Remote Sensing Newsletter is published quarterly by the Geoscience and Remote SensingSociety of the Institute of Electrical and Electronics Engineers, Inc., Headquarters: 3 Park Avenue, 17th floor,New York, NY 10016-5997. $1.00 per member per year (included in Society fee) for each member of the Geosci-ence and Remote Sensing Society. Printed in U.S.A. Periodicals postage paid at New York, NY and at additionalmailing offices. Postmaster: Send address changes to IEEE Geoscience and Remote Sensing Society Newsletter,IEEE, 445 Hoes Lane, Piscataway, NJ 08854.© 2001 IEEE. Permission to copy without fee all or part of any material without a copyright notice is granted pro-vided that the copies are not made or distributed for direct commercial advantage, and the title of the publicationand its date appear on each copy. To copy material with a copyright notice requires special permission. Please di-rect all inquiries or requests to the IEEE Copyrights Manager.IEEE Customer Service Phone: +1 732 981 1393, Fax:+1 732 981 9667.
IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 3
This issue of our Society’s Newsletter contains three majorarticles and a number of reports and timely news items. First isan industrial profile of GAMMA Remote Sensing AG of Swit-
zerland, focusing on their activities in SAR processing, inter-ferometry and related applications, including a number of in-teresting images. The second is a feature article describing theobjectives and planned implementation of the European SpaceAgency’s Soil Moisture and Ocean Salinity (SMOS) missionscheduled for launch in 2005. This Earth Explorer Opportunitymission uses L-band microwave imaging by aperture synthesisin order to provide the spatial resolution needed for mappingsoil moisture and ocean salinity. Third, this issue contains a re-port by the organizing committee of the First International Mi-crowave Radiometer Calibration Workshop, chaired by PaulRacette and held in October 2000 in College Park, Maryland.This workshop provided a forum for discussion of important is-sues in radiometer calibration standards and techniques, forboth current and future needs.
In the timely news items, we are proud to announce thatseven GRS-S members were elected to the grade of Fellow of
Steven C. ReisingDepartment of Electrical andComputer Engineering
113B Knowles EngineeringBuilding
University of MassachusettsAmherst, MA 01003-4410TEL: 413.577.0697FAX: 413.545.4652E-Mail: [email protected]
Editor's Comments
President's Message
Do national economies influence the expenditures in remotesensing and in remote sensing programs? The question is rhe-torical; they surely do, but how? At present the economy in Eu-rope is still growing, in Japan it is on a stable low, and the USeconomy is expected to slow down, while the economies in anumber of growing countries are rapidly rising. It can be ex-pected that industry is reacting rather quickly, while the re-sponse of public and government agencies will lag by severalyears. Usually space programs are less affected because theyare planned and undertaken in five- to ten-year time frames.The result of these considerations is that we need to pay carefulattention to the long-range programs and the employment pros-pects for engineers in remote sensing. Our proposals have to bemore attractive than those in other disciplines. Overall I do not
expect that remote sensing will be severely cut in the near fu-ture, but it will also not unexpectedly rise.
Our IGARSS ‘01 this year in Sydney will have an interest-ing program, and it will definitely have an Australian flavor. Itis the first time that our symposium will be held on this conti-nent. The Australian remote sensing community is relativelystrong. Remote sensing is required for the detection, monitor-ing and exploitation of resources, for infrastructure planningand for surveillance of the environment. This gives our col-leagues in Australia a strong mandate and a good position. Ilook forward to meeting many of you in Sydney in July.
Recently our IEEE GRS-S members encountered a problemwith access to papers in the IEEE Explore archive. The accessis limited to the last two years. This will be discussed at theAdCom meetings and with IEEE headquarters in order to find aconvenient solution.
Werner WiesbeckInstitute for Microwaves and
ElectronicsUniversity of KarlsruheKaiserstr.12D 76 128 KarlsruheGermanyTel.: +49-721-608-2522Fax: +49-721-69 18 65E-Mail: werner.wiesbeck@
etec.uni-karlsruche.de
Cover Figure InformationTop left: Detailed view of one segment of the MIRASantenna array including eight antenna/receiver elements(courtesy of EADS CASA Espacio).
Top right: Artist’s view of the SMOS satellite (courtesyof EADS CASA Espacio).
Bottom: The Proteus platform used for SMOS (courtesyof CNES and Alcatel Space Industries).
(See the article beginning on p. 11 for details.)
continued on page 4
continued on page 4
4 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
Steven C. Reising, EditorDepartment of Electrical and ComputerEngineering113B Knowles Engineering BuildingUniversity of MassachusettsAmherst, MA 01003-4410TEL: 413-577-0697FAX: 413-545-4652E-Mail: [email protected]
Edward J. Kim, Associate Editor forOrganizational and Industrial ProfilesBuilding 33, Room A426NASA Goddard Space Flight CenterMail Stop 975Greenbelt, MD 20771TEL: 301-614-5653FAX: 301-614-5558E-Mail: [email protected]
Adriano J. Camps,Associate Editor for European AffairsDepartment of Signal Theory andCommunicationsPolytechnic University of Catalonia,Campus Nord D4-01608034 Barcelona, SPAINTEL: (34)-93.401.60.85FAX: (34)-93.401.72.32E-Mail: [email protected]
Stephen J. Frasier,Associate Editor for University ProfilesDepartment of Electrical and ComputerEngineering113D Knowles Engineering BuildingUniversity of MassachusettsAmherst, MA 01003-4410TEL: 413-545-4582FAX: 413-545-4652E-Mail: [email protected]
Newsletter Editorial Board Members:
The GRS-S AdCom is presently discussing the rapidpublication of short papers. Under discussion are letters orcommunications to the Transactions or as separate letters,somewhat like what IEEE MTT has or IEEE AP-S is pre-paring to publish. One of our major problems in publica-tions is that many of the papers are excessively long. Thisleads, at a given page budget, to a rather high rejection rate.On the other hand, this may also be the reason for the excel-lent citation ratings of our Transactions, compared to com-peting journals. There is no question that our Transactionsare the leading journal for the dissemination of geoscienceand remote sensing research and operational results. It isthe forum for the discussion of new technologies and up-coming major problems.
I wish you all a good spring, and I hope to see many ofyou in Sydney.
Werner WiesbeckPresident GRS-S
President's Messagecontinued from page 3
the IEEE, effective January 1, 2001. Secondly, theGRS-S AdCom announces the election of two new mem-bers for 2001 and calls for nominations for this year’selections. The two new AdCom members are Prof. BillEmery of the Laboratory for Atmospheric and SpacePhysics at the University of Colorado at Boulder and Dr.Verne Kaupp, Director of the Alaska SAR Facility at theUniversity of Alaska Fairbanks, who is General Chair-man of IGARSS 2004, to be held in Anchorage. In addi-tion, the GRS-S announces the expansion of its team withthe addition of Ms. Lisa Ostendorf as Director of Infor-mation Services, to complement the work of Ms. TammyStein, the GRS-S Director of Conferences. Please join usin welcoming Lisa Ostendorf and thanking Tammy Steinfor her continued top-notch work to meet the needs of ourSociety. In his President’s Message, Werner Wiesbeckdiscusses economic influences on the remote sensingbusiness, the AdCom’s discussions on the rapid publica-tion of short papers to augment our excellent Transac-tions, and the upcoming IGARSS 2001, the first on theAustralian continent. As he does, I look forward to seeingmany of you in Sydney!
Editor's Commentscontinued from page 3
IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 5
2001 AdCom Members' Names and AddressesDr. Werner Wiesbeck (AdCom 2001-2003)President, IEEE GRS-SUniversity of KarlsruheInstitute for High Frequency and ElectronicsKaiserstrasse 1276128 KarlsruheGERMANYPhone: +49 721 608 2522 (or 7729)FAX: +49 721 691 865E Mail: [email protected]
Mr. Charles A. Luther (AdCom 1999-2001)GRS-S Executive Vice PresidentOffice of Naval Research800 N. Quincy StreetArlington, VA 22217USAPhone: 703 696 4123FAX: 703 696 2710E Mail: [email protected]
Dr. Thomas J. Jackson (AdCom 1999-2001)GRS-S SecretaryUSDA ARS Hydrology Lab104 Bldg 007 BARC WestBeltsville, MD 20705USAPhone: 301 504 8511FAX: 301 504 8931E Mail: [email protected]
Dr. Melba M. Crawford (AdCom 2000-2002)GRS-S VP for Professional ActivitiesCenter for Space Research3925 W. Braker Lane, Suite 2000The University of Texas at AustinAustin, TX 78712-5321USAPhone: 512 471 7993FAX: 512 471 3570E Mail: [email protected]
Dr. Albin J. Gasiewski (AdCom 1999-2001)GRS-S VP for Technical ActivitiesNOAA Environmental Technology Lab325 Broadway R/ET1Boulder, CO 80305USAPhone: 303 497 7275FAX: 303 497 3577E Mail: [email protected]
Dr. James A. GatlinGRS-S VP for Operations and Finance and Directorof Finance13420 Idlewild Dr.Bowie, MD 20715USAPhone: 301 286 6680FAX: 301 286 0232E Mail: [email protected]
Dr. Karen M. St. Germain (AdCom 2000-2002)GRS-S VP for Meetings and SymposiaNRL Remote Sensing Division, Code 72234555 Overlook Avenue, SWWashington, DC 20375-5351USAPhone: 202 767 3443FAX: 202 767 9194E Mail: [email protected]
Dr. Jon A. Benediktsson (AdCom 2000-2002)Department of Electrical and Computer EngineeringUniversity of IcelandHjardarhaga 2-6107 Reykjavik IcelandPhone: +354 525 4670FAX: +354 525 4632E-Mail: [email protected]
Dr. Andrew J. Blanchard (AdCom 1999-2001)College of Engineering / CSUniversity of Texas at DallasP.O. Box 830688 EC-32Richardson, TX 75083USAPhone: 972 883 4122FAX: 972 883 2813E Mail: [email protected]
Dr. Keith R. CarverHonorary Life MemberUniversity of MassachusettsDept. of Electrical & Computer EngineeringAmherst, MA 01003USAPhone: 413 545 1665FAX: 413 545 4611E Mail: [email protected]
Dr. William Emery (AdCom 2001-2003)Aerospace Engineering Sciences Dept.CCAR Box 431University of ColoradoBoulder, CO 80309Phone: 303 492 8591Fax: 303 492 2825E Mail: [email protected]
Dr. David G. Goodenough (AdCom 2000-2002)Pacific Forestry CentreNatural Resources Canada506 West Burnside RoadVictoria, BC V8Z 1M5CANADAPhone: 250 363 0776FAX: 250 363 0775E Mail: [email protected]
Dr. Martti T. Hallikainen (AdCom 2001-2003)Helsinki University of TechnologyLaboratory of Space TechnologyP. O. Box 3000FIN 02015 HUTFINLANDPhone: +358 9 451 2371FAX: +358 9 451 2898E Mail: [email protected]
Dr. Nahid KhazeniePast President, IEEE GRS-S8509 Capo Ct.Vienna, VA 22182USAPhone: 703 917 8655FAX: 703 917 8656E Mail: [email protected]
Dr. Alberto Moreira (AdCom 1999-2001)German Aerospace Center (DLR)Microwave and Radar Systems InstituteDept. SAR-TechnologyP.O. Box 11 1682230 Wessling, GermanyPhone: +49 8153 28 2360Fax: + 49 8153 28 1449Email: [email protected]
Prof. Ram M. NarayananDirector of Corporate RelationsUniversity of Nebraska LincolnDept. of Electrical Engineering209N Walter Scott Engineering CenterP. O. Box 880511Lincoln, NE 68588-0511USAPhone: 402 472 5141FAX: 402 472 4732E Mail: [email protected]
Dr. Kamal Sarabandi (AdCom 2001-2003)Dept. of Electrical Eng. & Computer ScienceAnn Arbor, MI 48109-2122USAPhone: 734 936 1575FAX: 734 647 2106E Mail: [email protected]
Dr. James A. SmithTransactions Editor-ElectCode 920NASA Goddard Space Flight CenterGreenbelt, MD 20771Phone: 301 614 6020FAX: 301 614 6015E Mail: [email protected]
Dr. Kiyo TomiyasuHonorary Life MemberLockheed Martin Corp.366 Hilltop RoadPaoli, PA 19301 1211USAPhone: 610 531 5740FAX: 610-531-1190E Mail: [email protected];[email protected]
Dr. Leung TsangTransactions EditorUniversity of WashingtonDepartment of Electrical Engineering, Box 352500Seattle, WA 98195USAPhone: 206 685 7537FAX: 206 543 3842E Mail: [email protected]
Dr. Fawwaz T. UlabyHonorary Life MemberThe University of Michigan4080 Fleming BuildingAnn Arbor, MI 48109-1340USAPhone: 734-764-1185FAX: 734-763-0085E Mail: [email protected]
Dr. David Weissman (AdCom 2000-2002)Hofstra University104 Weed HallHempstead, NY 11549Phone: 516 463 5546Fax: 516 269 5920Email: [email protected]
Ms. Tammy SteinDirector of ConferencesIEEE Geoscience and Remote Sensing Society17906 St Emilion CourtSpring, Texas 77379USAPhone: 281 251 6067FAX: 281 251 6068E Mail: [email protected]
Ms. Lisa OstendorfDirector of Information ServicesIEEE Geoscience and Remote Sensing Society63 Live Oak LaneStafford, VA 22554Phone: 540 658 1676FAX: 540 658 1686E Mail: [email protected]
Dr. Steven C. ReisingNewsletter EditorDepartment of Electrical and Computer Engineering113 Knowles Engineering BuildingUniversity of MassachusettsAmherst, MA 01003-4410USAPhone: 413 577 0697FAX: 413 545 4652E mail: [email protected]
Dr. R. Keith RaneyGRS-S Rep. to Soc. on Social Implications ofTechnologyJohns Hopkins Univ. Applied Physics LabSpace Dept.Johns Hopkins Rd.Laurel, MD 20723-6099USAPhone: 240-228-5384FAX: 240 228-5548E Mail: [email protected]
Dr. John A. ReaganPACE Rep.University of ArizonaECE Dept., Bldg. 104, Rm. 230Tucson, AZ 85721 0104USAPhone: 520 621 6193FAX: 520 621 8076E Mail: [email protected]
Dr. Anthony K. MilneIGARSS01 General ChairmanUniversity of New South WalesOffice of Postgraduate StudySydney, NSW 2052AUSTRALIAPhone: 61 2 9385 2731FAX: 61 2 9385 3733E Mail: [email protected]
Dr. Ellsworth LeDrewIGARSS02 General ChairmanUniversity of WaterlooGeography Department200 University Ave. WestWaterloo, Ontario N2L 3G1CANADAPhone: 519 888 4567 x 2783FAX: 519 888 6768E-Mail: [email protected]
Dr. Didier MassonnetIGARSS03 General ChairmanCNES18 Avenue E BelinToulouse Cedex 31401FRANCEPhone:l: +33 5 .61273418FAX: +33 5 61273167E-Mail: [email protected]
Dr. Verne Kaupp (AdCom 2001-2003)IGARSS04 General ChairmanAlaska SAR FacilityUniversity of Alaska Fairbanks903 Koyukuk Dr., P. O. Box 757320Fairbanks, Alaska 99775-7320Phone: 907 474 7263FAX: 907 474 6441E-Mail: [email protected]
Dr. Wooil M. MoonIGARSS05 General ChairmanSeoul National UniversityDept. of Earth System ScienceKwanak-gu Shilim-dong San 56-1Seoul, 151-742KOREAPhone: +822 880 8898FAX:E-Mail: [email protected]
INDUSTRIAL PROFILE
GAMMA Remote Sensing AGUrs Wegmüller, Charles Werner, Tazio Strozzi, and Andreas WiesmannGamma Remote Sensing, Thunstrasse 130, CH-3074 Muri, Switzerlandtel +41-31-9517005, [email protected], http://www.gamma-rs.ch
Who is GAMMA ?GAMMA Remote Sensing Research and Consulting AG
(GAMMA) is a Swiss corporation (Aktiengesellschaft - AG). Itwas founded in January 1995 and is located in Muri near Bern,Switzerland. GAMMA’s primary business elements are re-search and development, processing and adding value to re-mote sensing data, license sales for its commercial processingsoftware, and Earth Observation (EO) data distribution. GAM-MA is well integrated in the remote sensing research commu-nity and offers commercial services and software licenses. Thismaintains GAMMA’s technical competence and provides in-sight into customer requirements for information and tools.
The key personnel of GAMMA have extensive experiencein scientific research on synthetic aperture radar (SAR) andinterferometric signal processing, active and passive micro-wave remote sensing techniques, theoretical and empiricalmodeling, and applications development. GAMMA’s compe-tence encompasses technical specialties such as SAR process-ing, interferometry, differential interferometry, geocoding,
and mosaicing as well as fully integrated product generationfrom EO data. Typical products are digital elevation models,geophysical displacement maps, hazard maps and land useproducts such as forest and crop maps.
ActivitiesGAMMA is involved in research projects with the Euro-
pean Space Agency and the European Community (EC), aswell as with national projects, and cooperates with partners atuniversities, public institutes, and private companies. Exam-ples of our activities are described in the following paragraphs.
The European Forest Observations using Radars(EUFORA) Project was conducted by partners from five Euro-pean countries in the framework of the EC Environment andClimate Program. EUFORA’s main objectives were to evalu-ate the most advanced radar remote sensing research results inthe context of forest information required in environmental andclimate studies as well as forest management operations, tovalidate methods and results at different European sites, and todefine unified methods applicable in a pre-operational stage.GAMMA’s involvement was primarily in the methodologicaldevelopment and application of forest mapping and parameterretrievals using SAR interferometry. Results included a refinedmethodology for land use classification based oninterferometric coherence and multi-temporal backscatter im-ages. The methodology was applied and validated at sites inSwitzerland (Figure 1), France and Finland, confirming the po-tential of the technique [1].
In order to provide access to the potential of SARinterferometric signatures to a wider community, Spot Image(France) and GAMMA developed the ERS Tandem CoherenceProduct, which was made available as a commercial product inlate 1999. The Coherence Product consists of data layers calcu-lated from ERS Tandem acquisitions, including calibratedSAR backscattering coefficients, coherence, and temporalbackscatter change. Image data and auxiliary information areprovided in the Digital Image MAP (DIMAP) metadata stan-dard based on the eXtended Mark-up Language (XML) andGEOTIFF (an extension to the TIFF format that allows auto-matic geopositionning of images in Geographic InformationSystem (GIS) software), the future format for SPOT satellitedata. An impressive example of the usefulness of the Coher-ence Product was the Storm Forest Damage Mapping con-
6 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
Figure 1: ERS SAR interferometric land-use map for Bern,Switzerland. ERS Data Copyright ESA, Processing by GAMMA.
ducted in early 2000 for areas ofSwitzerland (Figure 2) and France.
A much larger forest map was gener-ated as part of the SIBERIA Project, con-ducted again in the context of the ECEnvironment and Climate Program bypartners from eight European countries.GAMMA’s main contributions were inthe methodological development and theoperational Japanese Earth ResourcesSatellite (JERS) SAR data processing[2-3]. In the framework of this project,GAMMA conducted full resolution SARprocessing of more than 600 JERSscenes. The processing included abso-lute radiometric cal ibrat ion andgeocoding. A large JERS mosaic isshown in Figure 3. Where available,interferometric processing of acquisi-tions from consecutive repeat-orbits was conducted. The JERSL-band interferometric signatures contain interesting land useinformation, as demonstrated in Figure 4, a composite of the44-day coherence (red), average backscattering coefficient(green) and backscatter change (blue).
During the last few years, GAMMA has been heavily in-volved in the development of differential SAR interferometryfor land surface deformation mapping. Impressive results in-clude maps of the ground water extraction-related subsidenceof Mexico City (Figure 5, [4]) and Bologna (Figure 6, [5]) aswell as of the complex temporal and spatial deformations ob-
served for an active coal mining area [6]. In the case of slow de-formations, millimeter accuracy was achieved by combination(“stacking”) of multiple interferograms. Deformation mappinghas recently evolved into a relatively mature application withgood potential for commercial use.
GAMMA SoftwareSoftware development is another focus of GAMMA’s
work, encompassing the entire processing chain from SAR rawdata to products such as digital elevation models from ERS orJERS SAR interferometry, the generation of maps of millime-ter to decimeter surface displacement with differential SAR in-terferometry, large area mosaicing, and land use maps.
The software is grouped into the following four packages:
IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 7
Figure 2: Forest damage (orangeareas) caused by the “Lothar”storm in December 1999, asmapped by multi-temporal ERSSAR interferometry. Raw datacourtesy of ESA. Photograph andProcessing by GAMMA.
Figure 3: Mosaic of JERS L-band backscattering coefficient for Sibe-ria (Equiangular coordinates, 51° to 64° North, 86° to 115° East).Raw data courtesy of DLR and NASDA, Processing by GAMMA.
Figure 4: RGB composite of JERS interferometric signatures (red:coherence, green backscattering, blue: backscatter ratio) for a 40 x34 km2 section of Siberia. Raw data courtesy of DLR and NASDA,Processing by GAMMA.
• Modular SAR Processor (MSP)• Interferometric SAR Processor (ISP)• Different ia l Interferometry and Geocoding
(DIFF&GEO)• Land Application Tools (LAT)
all of which can run on a variety of computer platforms.Full-frame SAR processing times for ERS and JERS are
well below one hour on today’s workstations and PCs, in-cluding processing parameter estimation, autofocus, radio-metric calibration, and multi-looking. The softwareprocesses data from spaceborne and airborne SARs, includ-ing ERS-1/2, JERS, RADARSAT, and SIR-C. It fully sup-ports the data formats provided by the responsible spaceagencies and their designated processing and archiving fa-cilities. The main processing sequences are complementedby parameter estimation and quality control programs, in-cluding display programs and utilities based on open sourcetechnology for convenient access to input data, intermediateproducts, and final results [7-8]. Recently, the offset estima-tion programs were further enhanced to allow coherence andfeature tracking for monitoring fast glacier motion and largeseismic displacements. An application of this new function-ality was the monitoring of a glacier surge in Greenland [9].
More detailed information on GAMMA’s activities may befound at http://www.gamma-rs.ch.
References[1] Strozzi T., P. B. G. Dammert, U. Wegmüller, J-M. Marti-nez, A. Beaudoin, J. Askne, and M. Hallikainen, Landusemapping with ERS SAR interferometry, IEEE Trans. Geosci.Remote Sensing, Vol. 38, No. 2, pp. 766-775, 2000.
[2] Wiesmann A., Wegmüller U., T. Strozzi, and C. Werner,“JERS INSAR coherence over Siberian boreal forest”, Pro-ceedings of ERS-ENVISAT Symposium, Gothenburg, Swe-den, 16-20 Oct. 2000.
[3] Wiesmann A., L. Demargne, F. Ribbes, M. Honikel, H.Yésou, and U. Wegmüller , “Forest storm damage assessment
8 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
Figure 5: Mexico City: ERS SAR interferometric subsidence mapfor second half of 1996 (5cm/year subsidence per color cycle) com-pared to contour lines of equal ground sinking velocity calculatedfrom leveling campaigns in 1994 and 1996 (provided by Vega). ERSData Copyright ESA, Processing by GAMMA.
Figure 6: ERS interferometric subsidence maps generated for (a)1992-1993 and (b) 1997-1998 indicate a reduction in land subsi-dence velocity at Bologna, Italy. ERS Data Copyright ESA, Pro-cessing by GAMMA.
a
b
with ERS Tandem data”, Proceedings of ERS-ENVISATSymposium, Gothenburg, Sweden, 16-20 Oct. 2000.
[4] Strozzi T. and U. Wegmüller, Land Subsidence in MexicoCity Mapped by ERS Differential SAR Interferometry, Pro-ceedings of IGARSS’99, Hamburg, 28 June - 2 July 1999.
[5] Strozzi T., U. Wegmüller, and G. Bitelli, “DifferentialSAR interferometry for land subsidence mapping in Bolo-gna”, Proceedings of SISOLS 2000, Ravenna, Italy, 25 -29September 2000.
[6] Wegmüller U., T. Strozzi, C. Werner, A. Wiesmann, N.Benecke, and V. Spreckels, “Monitoring of mining-inducedsurface deformation in the Ruhrgebiet (Germany) with SARinterferometry”, Proceedings of IGARSS 2000, Honolulu,USA, 24-28 July 2000.
[7] Wegmüller U., SAR Processing, Interferometry, Differ-ential Interferometry and Geocoding Software, EUSAR’98,25-27 May, Friedrichshafen, Germany, VDE-Verlag, ISBN3-8007-2359-X, pp. 145-148, 1998.
[8] Werner C., U. Wegmüller, T. Strozzi, and A. Wiesmann,“Gamma SAR and Interferometric Processing Software”, Pro-ceedings of ERS-ENVISAT Symposium, Gothenburg, Swe-den, 16-20 Oct. 2000.
[9] Strozzi T., A. Luckman, and T. Murray, “The evolution ofa glacier surge observed with the ERS satellites”, Proceedingsof ERS-ENVISAT Symposium, Gothenburg, Sweden, 16-20Oct. 2000.
IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 9
GRS-S Members Elected to the Grade of Fellowof the IEEE, January 1, 2001
Lawrence CarinDuke University, Durham, NCFor the development of short pulse scattering techniques todetect objects in clutter that have led to practical methods fordetection of buried land mines.
Alfred Tieh Chun ChangNASA Goddard Space Flight Center, Greenbelt, MDFor contributions to the development of microwave remotesensing of rain and snow.
Shane Robert CloudeApplied Electromagnetics, St. Andrews, ScotlandFor contributions to the development of polarimetry and itsapplications in wide-band radar and optical remote sensing.
Ram Mohan NarayananUniversity of Nebraska, Lincoln, NEFor contributions to the development of coherentultra-wideband random noise radar systems forhigh-resolution imaging applications.
Christopher S. RufUniversity of Michigan, Ann Arbor, MIFor contributions in the development,calibration, and remote sensing applications ofmicrowave radiometers.
Thomas J. SchmuggeU.S. Department of Agriculture, Beltsville, MDFor contributions to the development andapplication of passive microwave remote sensingto the study of soil moisture and texture.
Edgeworth Rupert WestwaterUniversity of Colorado, Boulder, COFor theoretical and experimental contributions tothe development of radiometers for atmosphericwater vapor and temperature profiling.
Introducing New GRS-S AdCom Members for 2001A native of Honolulu, Wil-
liam (Bill) Emery received hisPh.D. in Physical Oceanogra-phy from the University of Ha-waii in 1975. After working atTexas A&M University, hemoved to the OceanographyDepartment of the University ofBritish Columbia in 1978,where he created a satelliteoceanography facility and pro-gram. After a short period at theNational Center for Atmo-spheric Research (NCAR) he
moved to the University of Colorado at Boulder. He was ap-pointed full professor in Aerospace Engineering Sciences atthe University of Colorado in 1987. He is active in the analysisof satellite data for oceanography, meteorology and terrestrialvegetation. In addition, his group writes analysis software andestablishes/operates data systems for the distribution of satel-lite data received by their own antennas. He is a member of theLaboratory for Atmospheric and Space Physics (LASP), and afounding member of the Program in Oceanic and AtmosphericSciences (PAOS). He is a co-author of two textbooks on physi-cal oceanography, has translated three oceanographic booksfrom German to English and has authored over 120 refereedpublications. He is the oceanography and atmospheric scienceeditor of Remote Sensing of the Environment and the co-chiefeditor of Oceanic and Atmospheric Data Management. He is anactive consultant with Raytheon for the National Polar Or-biting Environmental Satellite System (NPOESS). He is also amember of the TOPEX/Poseidon and JASON altimeter satel-lite science working groups. He is the Principal Investigator onthe Student Reflected GPS Experiment (SuRGE) satellite pro-posed to NASA as a UnESS mission.
Verne H. Kaupp is Director and Chief Scientist of theAlaska SAR Facility (ASF). Dr. Kaupp is guiding ASF to focuson increasing the availability of SAR data to an expanding usercommunity. He has served as Professor of Electrical Engi-neering and conducted a successful research program, servedon various NASA teams and as an investigator for several Shut-tle Imaging Radar missions. Verne was Vice President of asmall research company and conducted numerous studies forboth foreign and domestic government agencies. Dr. Kauppgraduated from the University of Maryland with a BS in Phys-
ics. He was then employed bythe Denver office of the MartinMarietta Corporation to test andevaluate a microwave remotesensor—one of a suite of sen-sors known as the Earth Re-sources Experiment Package—installed on SKYLAB. Vernereceived the Doctor of Engi-neering degree in electrical en-gineering from the Universityof Kansas. He developed thefirst radar image simulation andapplied it to various topics. He
was a Professor of Electrical Engineering at the University ofArkansas, where he established a research program on radarimage simulation that was funded by NASA. He was a SIR-BPrincipal Investigator and a SIR-C Co-Investigator. He hasbeen a member of various NASA working groups and scienceteams. He performed classified research for the U.S. Govern-ment and conducted various studies under contract to severalJapanese Government agencies and corporations. He assumedthe position as Chief Scientist of the Alaska SAR Facility in1997. He also held the position of Research Professor in theGeophysical Institute, University of Alaska Fairbanks. In 1998Dr. Kaupp was selected as the Director and Chief Scientist ofthe Alaska SAR Facility after a national search. In this positionVerne has been instrumental in reorganizing the ASF and inshaping a vision that is consistent with the needs of both NASAand the University of Alaska Fairbanks. ASF acquires, pro-cesses, archives, and distributes vast quantities of SAR datafrom a suite of sensors for a user community consisting of bothlarge and small customers and programs. One example of alarge program is the Antarctic Mapping Mission conducted in1997 using the RADARSAT sensor. Most recently, he hasstarted a program that will facilitate the use of remote sensingdata in operational agencies across Alaska. He has held the firstworkshop for this program, which was attended by representa-tives of NASA, the Office of the Lieutenant Governor ofAlaska, Alaska State agencies (primarily decision makers), theacademic community and others. The goal of this series ofworkshops is to help Alaska benefit from the availability ofNASA technology and data. This is a major effort to demon-strate the applicability of NASA technology and research re-sults for solving the operational needs of Alaska.
10 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
Bill Emery Verne Kaupp
FEATURE ARTICLEESA’s Second Earth Explorer Opportunity Mission:
The Soil Moisture andOcean Salinity Mission – SMOS
P. Silvestrin(1), M. Berger(1), Y. H. Kerr(2), J. Font(3),1Earth Observation Future Programmes Department, ESA, Noordwijk, The Netherlands, Phone: +31 71 5653689,E-mail: [email protected]
2CESBIO, 18 av E. Belin, 31401, Toulouse, France, E-mail: [email protected] de Ciencies del Mar CSIC, P. Joan de Borbo s/n, 08039 Barcelona, Spain, E-mail: [email protected]
1. IntroductionThe European Space Agency (ESA) has selected the Soil
Moisture and Ocean Salinity (SMOS) mission for imple-mentation as the second mission in the line of Earth ExplorerOpportunity missions. These are intended to be very cost-ef-fective space missions, implemented on short timescales,possibly exploiting new development approaches and op-portunities for international cooperation. SMOS will belaunched in 2005 and will be realized with contributionsfrom the national space programs of France and Spain. Thispaper is intended to review the scientific rationale and tech-nical foundations of the SMOS mission and to outline themain elements addressed by ongoing studies.
2. Scientific Objectives of SMOSThe goal of the SMOS mission is to observe two key vari-
ables, namely soil moisture (SM) over land and ocean surfacesalinity (OS), by means of L-band microwave imaging radiom-etry. SMOS will also provide information on root zone soilmoisture, vegetation and biomass and contribute to research onthe cryosphere. It is expected that the knowledge of global dis-tribution of SM and OS at adequate spatial and temporal sam-pling will significantly enhance weather forecasting, climateand extreme event predictions.
SM plays a key role in the hydrological cycle and in vegeta-tion monitoring. The water and energy fluxes at the surface/at-mosphere interface strongly depend upon SM since SM drivesevaporation, infiltration and runoff. Moreover, SM in thevadose zone determines the rate of water uptake by vegetation.
OS plays an important role in the Northern Atlantic sub-polararea, where intrusions with low salinity influence the deepthermohaline circulation and the meridional heat transport. OSvariations also influence the near-surface dynamics of tropicaloceans, where rainfall modifies the buoyancy of the surfacelayer and the tropical ocean-atmosphere heat fluxes. OS and itsseasonal and inter-annual variabilities are thus key variables forthe water cycle and for the coupled ocean-atmosphere models.
SM and OS need to be mapped on a global scale and with ad-
equate spatial and temporal sampling. The SMOS mission isdesigned to provide this information for the first time. It willalso deliver information on vegetation water content and rootzone moisture, useful, for example, in crop yield forecasting.The main requirement for mapping SM from space is an accu-racy that is useful for hydrological and meteorological model-ing, coupled with an adequate temporal sampling. Recentstudies show that determining SM to 4% accuracy (volumetric)every three days is sufficient even in the presence of rain eventsand of quick dry-out sequences. The spatial resolution require-ments are linked to the applications and range from 50 - 100 kmfor global circulation models to 20 km or even less for hydrol-ogy and agronomy.
To achieve the SM retrieval requirements it is necessaryto account for the vegetation contribution to the radiometricsignal and to correct for topographic effects and surface tem-peratures. Observations of the brightness temperature atmultiple incidence angles allow one to retrieve SM even inthe presence of vegetation. In addition, mixed pixels, densevegetation, free bodies of water, dew and frost can be ac-counted for in the retrieval process. Once the surface SM isknown from the SMOS data it is possible to estimate rootzone SM. Observations during a hydrological event, e.g. adrying period, provide estimates of the corresponding sur-face hydraulic conductivity values.
The sensitivity of L-band radiometer measurements overthe ocean to surface salinity is well established. It is possible toobtain OS estimates if the other perturbing factors (roughness,wind, foam, sun glint, rain, etc.) can be accounted for or com-pensated. The sensitivity of the brightness temperature to salin-ity is about 0.5 K/psu (psu = practical salinity unit or approx.0.1%, or ppt) at a water temperature of 20 °C, decreasing toabout 0.25 K/psu at 0 °C. Since the sensitivity ofstate-of-the-art radiometers is ~1 K, individual observationscannot meet the requirements of the Global Ocean Data Assim-ilation Experiment (GODAE), which are: 0.1 psu accuracy;spatial resolution of 2° x 2°; revisit time of 10 days. However,these requirements could be met by spatially and temporally
IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 11
averaging SMOS observations, provided any systematic errorsare kept very low, e.g. by means of frequent calibrations. Indi-vidual observations allow sea surface salinity estimates ofabout 1 psu every 3 days, which is adequate for enclosed seaswith high salinity contrasts (e.g. the Baltic Sea).
3. The SMOS Concept: MicrowaveImaging Radiometry by ApertureSynthesis
Spaceborne microwave radiometry at L-band is a very effec-tive technique to observe SM and OS on a global scale. Othertechniques (higher frequency radiometers, SARs, optical sensors)suffer major drawbacks caused by cloud coverage, poor sensitiv-ity or various perturbing factors such as soil surface roughness andvegetation cover. Assuming that the surface temperature is knownby other means, the brightness temperature measurements pro-vided by the radiometer allow one to derive the surface emissivity.Over land, emissivity can be derived to the required accuracy ifsurface temperature is known to ~2 K, which is feasible with exist-ing models initialized by in-situ and remotely sensed data. Overthe oceans, one needs to account also for a number of strongly per-turbing effects, such as the azimuthal variation of emissivity withthe wind-induced roughness of the sea surface.
Operating the radiometer at L-band provides the maxi-mum sensitivity of emissivity to both SM and OS. However,antenna diameters of several meters are required to meet thespatial resolution requirement for SM mapping which, forthe design of SMOS, has been set at 50 km. A large real-ap-erture antenna on a low-Earth orbiting satellite poses a num-ber of practical difficulties. A problem arises from the needto achieve global coverage of the Earth within three days,implying that a large instrument swath is needed. Micro-wave imaging by aperture synthesis provides an effective al-ternative to more classical solutions, such as the use ofmechanically or electrically steered antennas and of push-broom instruments. This interferometric approach to micro-wave radiometry, inspired by the techniques developed inradio astronomy over several decades, is based on the use ofmany small antenna/receiver units, geometrically arrangedin order to sample the signal that would have been receivedby a real-aperture antenna. This sampling in the spatial do-main, enabled by the use of multiple antenna elements, pro-vides a scanning capability through a wide swath solelythrough (ground) signal processing.
The concept of L-band imaging radiometry with aperturesynthesis was first realized and validated in airborne cam-
paigns with the ESTAR (Elec-tronically Steered ThinnedArray Radiometer) instrumentdeveloped by NASA andUSDA at the University ofMassachusetts in the 1980s.ESTAR provides the requiredangular resolution in the flightdirection with a real aperture(by means of stick antennas)and with a synthetic aperture inthe cross-track direction. ForSMOS, a two-dimensional ap-erture synthesis concept wasdefined in detail during thepre-development phase of theMIRAS (Microwave ImagingRadiometer with Aperture Syn-thesis) instrument initiated byESA in 1993. This concept isbased on a Y-shaped symmetri-cal antenna array (cover page,top right). Each antenna arm isapproximately 4 m long andcontains at least 21 identicaland equally spaced antenna/re-ceiver elements. One elementat the center of the array oper-ates as a noise injection radi-ometer. To allow the antenna
12 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
Figure 1: Instantaneous field of view (FOV) for a representative configuration of SMOS. Thesubsatellite point and the intersection between antenna axis and Earth’s surface are shown by twosquares. The length of the dwell line determines the number of observations available for retrievingSM and OS.
array to be folded during launch, each arm is divided intothree segments. Each segment carries at least six antenna/re-ceiver elements, as well as calibration and support equipment(cover page, top left). The antenna arms are deployed in a syn-chronized manner shortly after launch. Ten elements, includ-ing the noise injection radiometer, are located on a fixedstructure, which also contains nine additional antenna/re-ceiver elements for redundancy.
To review the principles of interferometric radiometry, werefer to the case of two identical antenna/receiver elements lo-cated at the positions (x1, y1) and (x2, y2) in the XY plane. Thetwo receivers output two complex signals b1(t) and b2(t) (splitinto their I and Q components), which can be cross-correlatedto provide a sample of the so-called visibility function V(u,v)(in dimensions of temperature):
where (u1-2,v1-2) = (x2-x1, y2-y1)/λ is the antenna spacingnormalized by the wavelength (approximately 21 cm), (ξ,η) =(sin θ cos φ, sin θ sin φ) are the direction cosines with respectto the X and Y axes, F represents the Fourier transform be-tween the domains (ξ,η) and (u,v), B is the noise bandwidth(19 MHz for SMOS), Ω is the antenna beamwidth (expressedas a solid angle), TB is the brightness temperature of the re-ceived signal, G is the power gain of each receiver and kB isBoltzmann’s constant. This relationship can be inverted byusing a pseudo-inverse Fourier transform method to derivebrightness temperature from the visibility samples, which isthe fundamental concept for image reconstruction in theSMOS mission. When many additional antenna/receiver ele-ments are present, as on SMOS, performing the cross-correla-tions among all elements necessitates the use of severalthousand correlators, which must be implemented in digitalVLSI technology to keep power consumption to an accept-able level. The antenna element size and the need to minimizeantenna mutual couplings means that inter-antenna spacingcannot meet the Nyquist criterion in the spatial domain, so theradiometer field of view becomes constrained by aliasing ofthe Earth image. For SMOS a range of admissible inter-an-tenna spacing (approx. 0.8λ to 0.9λ) is currently being con-sidered for overall system optimization. In practice the usefulfield of view is also constrained by the pixel limits derivedfrom the spatial resolution requirements and by the need tohave enough pixels along the flight direction in order to en-sure a sufficient number of independent views of the sameEarth area to improve the retrieval of SM (Figure 1). In orderto extend the field of view, the antenna array is tilted with re-spect to nadir. This angle is being optimized jointly with theantenna spacing and the orbit parameters.
4. Main Instrument Characteristics andCalibration
Each antenna/receiver unit is based on a patch antenna with-out dielectric substrate with ~70º half-power beamwidth,directivity of ~8 dB and provides both H and V polarizationswith excel lent cross-polar izat ion character is t ics(copolar/crosspolar ratio > 25 dB). A single receiver chain perantenna element is available, so that each unit can operate in ei-ther H or V polarization upon command from a control unit. Ineach receiver the antenna signal is filtered to the selected band-width (1404 to 1423 MHz, in a region of the spectrum reservedfor passive measurements), amplified and finally sampled andconverted to a 1-bit digital signal. The output data stream, com-bining both I and Q components, is transmitted at a rate of ~130Mb/s to the correlator unit using an optical fiber link. Each ele-ment also receives (via a second optical fibre link) a cen-trally-generated reference clock signal in order to perform thefrequency down-conversion and the sampling with phase co-herence among all elements. Oversampling by approximately afactor of two with respect to the Nyquist criterion is achieved ineach receiver, which improves the radiometric sensitivity. Inthe correlator unit, after conversion from optical to electricalsignals, a massive bank of 1-bit/2-level correlators imple-mented in dedicated integrated circuits performs the cross-cor-relations among all signals. Horizontal and verticalpolarization images are interlaced, and the cross-correlationfor each polarization is performed over a ~0.3 s period. Up to 5images are then averaged, so two images (one per polarization)are available every ~3 s.
The radiometer calibration includes an on-board calibrationby injection of stable noise signals and a vicarious calibrationby periodic imaging of well-monitored and stable regions dur-ing the mission. To implement the former, each receiver inputis periodically connected first to a non-correlated noise sourceand then to a correlated noise source. With uncorrelated noise,the finite values at the correlator outputs (which ideally shouldbe null) provide an estimate of the offsets caused by thresholderrors in the analog-to-digital conversion. Correlated noise isinjected into groups of receivers to estimate other error terms,for instance, those caused by receiver mismatches. Vicariouscalibration will provide an absolute calibration of the radiome-ter. Several reference targets are under consideration, includ-ing stable and uniform areas in the Sargasso Sea and inAntarctica. An important pre-launch activity will be the veryprecise characterization of the radiation patterns of the antennaarray and of the transfer function of each receiver. The possibil-ity of using natural sources such as the sun or the moon as sup-plementary in-orbit calibration means is currently under study.
5. Satellite Design and Mission ProfileThe SMOS satellite design is based on the use of the exist-
ing Proteus generic platform (cover page, bottom) developedby CNES for a variety of missions, the first of which (Jason-1)
IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 13
( ) ( ) ( ) ( ) 2B*
1,2 1,2 1,2 1 2 2 2
T ,1 1 1,
2 1n
B
V (u ,v )= b t b t F ,k B G
Fξ η
ξ ηξ η
=
Ω − −
will be launched later this year. The platform main body is cu-bic with ~1 m sides and contains the equipment necessary tostore the on-board data (correlator outputs, monitoring andcalibration measurements, etc.), to power, monitor and con-trol the radiometer and to stabilize its operating temperature.Proteus also provides capabilities for orbit acquisition andmaintenance over the planned three-year lifetime (with a goalof five years) and for precise attitude control and determina-tion. The masses of the platform and the radiometer are ap-proximately 300 kg each.
The operational orbit is a sun-synchronous one with localsolar times of 6:00 a.m. and 6:00 p.m. at the equator crossing(“dawn-dusk orbit”). Such an orbit improves the mission per-formance, principally due to stable thermal conditions. The or-bital altitude is still the subject of detailed optimization, butwill be in the range 650 - 760 km. The satellite design is com-patible with several launch vehicles, e.g., the Rocket, PSLVand DNEPR.
6. ConclusionThe SMOS mission is currently undergoing an extended
feasibility and optimization study, to be completed at the end of2001. The implementation phase is planned to commence inmid-2002, on time for a launch in mid-2005. The study is sup-ported by the development of end-to-end performance simula-tion software, including detailed modeling of the radiometer,its calibration and the related ground image reconstruction. Thesoftware will include SM and OS retrieval algorithms at a laterstage, using the results of concurrent studies by European sci-
entific consortia. Measurement campaigns have been con-ducted to gather radiometric data necessary to improve seaemissivity models (e.g., with respect to the impact of wind andspray) and to refine the OS retrieval algorithms.
Breadboarding and testing of all the critical elements of theMIRAS radiometer will be completed soon, and the resultswill be used for optimization of the SMOS design. An im-proved breadboard is under preparation in order to demon-strate imaging capabilities. An airborne L-band imagingradiometer under development at the Helsinki University ofTechnology (Finland) is expected to provide a validation ofthe imaging and calibration processes applicable to theSMOS mission during 2001.
The SMOS mission has ambitious science objectives andchallenging technical requirements. However, its science fun-damentals are very solid, and the technical solutions proposedbuild upon the results of many years of research and develop-ment in Europe and elsewhere. It is expected that remote sens-ing with microwave radiometry by aperture synthesis, as willbe soon realized with SMOS, will enhance our knowledge ofthe land and ocean processes in a very significant manner.
AcknowledgmentsSMOS technical studies were and are performed by consor-
tium of European companies and institutes led by EADSCASA Espacio, Madrid. The contributions to the mission def-inition by the Universitat Politecnica de Catalunya (UPC,Spain) and by the CNRS (France) are also acknowledged. TheMIRAS technology development work was managed by M.Martin-Neira at the Payload Systems Division of ESA.
14 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
CALL FOR NOMINATIONS FOR THE GRS-SADMINISTRATIVE COMMITTEE
DEADLINE: MAY 31, 2001The Nominations Committee calls upon our membership to
nominate members to serve on the GRS-S AdCom. A nomi-nating petition carrying a minimum of five names of Soci-ety members, excluding students, shall automatically placethat nominee on the slate, although the Nominations Com-mittee may choose to include a name on the slate regardlessof the number of names on the nominating petition. Yournominees should confirm in writing their willingness tostand for election.
A brief biography of the nominee, similar to that used forTGARS authors, will be required and should be submittedwith the nominating petition by May 31, 2001, to the GRS-SNominations Committee, c/o Martti Hallikainen, Nomina-tions Chair, Helsinki University of Technology, Laboratory
of Space Technology, P.O. Box 3000, 02015 HUT, Finland;Fax: +358.9.451.2898; E-mail: [email protected].
The slate derived by the Nominations Committee shall bepresented to the Society membership at large via mail ballot,and the three candidates receiving the greatest number of votesshall be elected. The Administrative Committee shall hold anAnnual Meeting in November 2001 after the results of this voteare known, at which time elections will be held to fill the re-maining two regular vacancies in the Administrative Commit-tee to occur on January 1, 2002.
Our AdCom consists of 15 elected persons, each of whomserves for three years. Their terms are overlapping to assurecontinuity. Additional information on the Society and theAdCom is available at http://ewh.ieee.org/soc/grss.
IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 15
The First International Microwave RadiometerCalibration Workshop
Submitted by the µCal organizing team:
General Chair: Paul Racette - NASA/GSFCCo-Chair: Martti Hallikainen - Helsinki
University of TechnologyConference Chair: Jeff Piepmeier -
NASA/GSFCGRS-S Representative: Jon Atli Benediktsson -
University of IcelandTechnical Program Committee
Al Gasiewski - NOAA/ETLTim Hewison - UK Meterological OfficeJim Randa - NIST/BoulderJim Shuie - NASA/GSFCNiels Skou - Technical University of DenmarkCal Swift - UMASSAlan Tanner - NASA/JPL
Publications, Publicity, and Public Relations CommitteeEd Kim - NASA/GSFCMaria Lecha - NASA/GSFC
Finance CommitteeCathy Long - NASA/GSFC
In recognition of the challenges posed by cali-bration of microwave remote sensing instrumen-tation and its importance to society at large, theNational Aeronautics and Space Administrationand the IEEE Geoscience and Remote SensingSociety co-sponsored the First International Mi-
crowave Radiometer Calibration Workshop (µCal 2000). Theworkshop was held on October 30 and 31, 2000 at the Univer-sity of Maryland Inn and Conference Center.
Remote sensing data are playing an ever more importantrole in the discussion and formulation of international pol-icy. As natural resources become scarcer and climate changeaffects more people, the geopolitical importance of remotesensing measurements will increase. Accurate calibration isimperative for the proper application of remotely sensedgeophysical data to public policy decision-making. Calibra-tion of remote sensing instrumentation is of primary concernto the GRS-S. During the past decade we have witnessedmany advances in microwave remote sensing technologies.Airborne interferometry is maturing, and spaceborne inter-
GRS-S Expands Team To Meet ChangingNeeds of Society
IEEE GRS-S welcomes Ms.Lisa Ostendorf to the team as Di-rector of Information Services tocomplement the existing posi-tion of Director of Conferences,retained by Ms. Tammy Stein.Ms. Ostendorf spent much of thelast ten years working for the Na-tional Aeronautics and SpaceAdministration. After receivingher Bachelor of Business Ad-ministration Degree from theUniversity of Texas in 1989, shemoved to the Washington, D.C.
area and started working on the Space Station Freedom Pro-gram in 1990. She moved to the Office of Earth Science in 1994and managed the Mission To Planet Earth Education and Out-
reach Program. Her accomplishments in strategic planning,implementation of geographically dispersed and complex pro-grams, budget and financial management, and program evalua-tion have been recognized with numerous NASA and MTPEawards including the NASA Headquarters Exceptional Perfor-mance Award (1996) and the NASA Superior Accomplish-ment Award for Special Act or Service (1995, 1991). Ms.Ostendorf has authored six papers in refereed publications, in-cluding the most recent submission to IGARSS 2000.
The Director of Information Services position has beenfilled to reflect the growth and changing needs of the Society.Ms. Ostendorf will be responsible for Society marketing andmedia relations, exhibition management, conference abstractprocessing, advance and final program production, proceed-ings preparation, and new GRS-S initiatives.
Editor's Note: Ms. Ostendorf's contact information can befound on page 5.
Lisa Ostendorf
16 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
ometry is about to become a reality with the development ofthe European Space Agency’s Soil Moisture and Ocean Sa-linity mission (SMOS). Polarimetric radiometry is demon-strating high potential to provide unique and valuableenvironmental information. Direct-to-digital detection atthe antenna terminals is another developing technique,though still in its infancy. For traditional measurement tech-niques as well as these newer methods, continual improve-ment of calibration remains a challenge.
There were 99 registered attendees at the meeting, 80%from North America and 20% from Europe. Approximately tenpercent (10%) of the attendees were graduate students.Twenty-nine (29) oral presentations and thirteen (13) posterswere presented – two-thirds from North America and one-thirdfrom Europe. Thirty-eight percent (38%) of the total presenta-tions were from universities, 5% from industry, and the re-maining 54% from both U.S. and European governmentagencies. Over one-third of the attendees were IEEE members.
Pre-workshop SurveyIn a pre-workshop Web-based survey, attendees of the
meeting were asked about the state of the art of calibration, themost challenging aspects of calibration, and anticipated cali-bration requirements in the next 10 years. Twenty-eight re-sponses were received, representing about one quarter of theworkshop attendees. Partial results of the survey are pre-sented in Figure 1. The results indicate that nearly an order ofmagnitude improvement in the calibration accuracy of micro-wave radiometers may be needed in the next 10 years. The re-
spondents were divided when asked to identify the most chal-lenging aspects of calibration and responded as follows: 38%calibration reference design, 33% receiver thermal design,25% antenna characterization, and 4% (1 respondent) re-ceiver linearity. Although the survey respondents represent asmall sample of the engineers and scientists involved in mi-crowave radiometry, the presentations given during the work-shop affirmed the results of the survey.
Working SessionsFour non-overlapping working sessions were conducted
over the two-day period, during which attendees delivered29 presentations. The workshop commenced on Mondaymorning with a discussion of the calibration requirementsand verification techniques for space-based radiometers.The broad scope of the presentations and the opportunity forthorough question-and-answer sessions set the stage for pro-ductive and meaningful discussions. On Monday afternoonthe workshop focused on calibration standards and refer-ences. A consensus of workshop attendees indicated a needfor clarification and standardization of terminology used forcharacterizing radiometer systems. On Tuesday morning,discussion turned to the design and calibration of groundbased and airborne radiometers. The presentations illus-trated the difficulty and subtle complexities of radiometercalibration. The audience understood the challenges facedby the presenters in calibrating radiometer systems. The fi-nal afternoon of the workshop was dedicated to the calibra-tion of correlation-based radiometers. The discussions
Figure 1: Results from the pre-workshop survey.
(a) What level of accuracy is commonly achieved bymodern (i.e. existing) microwave radiometers?
(b) What level of measurement accuracy and resolution(sensitivity) do you anticipate needing in 10 years or more?
IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 17
ranged from the importance of andmethodologies for characterizingantenna arrays to the design of cali-brated correlation noise sources.The challenges associated with cal-ib ra t ing in te r fe romet r ic andpolarimetric radiometer systemswere apparent from the in-depthdetails presented.
Poster SessionThirteen posters were presented
during two extended afternoon inter-active sessions. The posters covereda wide range of calibration issues, in-cluding calibration algorithm de-sign, characterization of airborneand ground-based radiometers, cali-bration references, and implementa-tion of the tipping-curve calibrationtechnique. Besides providing a fo-rum to accommodate additional pre-sentations, the extended afternoon breaks were a time duringwhich colleagues could discuss and debate issues relevant tocalibration.
Invited PresentationsA buffet lunch was catered each day during which
in-depth presentations were given by Prof. Chris Ruf and Dr.Yan Kerr. The talks complemented one another well and ad-dressed some of the major themes of the workshop. Duringthe first talk, Prof. Ruf presented a new method for calibra-tion of the TOPEX radiometer by using the coldest observa-tions over the sea surface as a vicarious calibrationreference. In the presentation Dr. Ruf demonstrated the util-
ity of vicarious references for the analysis and verificationof radiometer system calibration by tracking a slow drift inthe calibration of the TOPEX microwave radiometer. Dr.Kerr presented an overview of the ESA SMOS (Soil Mois-ture and Ocean Salinity) interferometric L-band radiometermission and the calibration requirements derived from thescience for the mission. He explained ESA’s approach tomeeting those requirements.
ConclusionOverall, the workshop was a smashing success. Clearly
calibration is a common element and significant challengein microwave radiometer design and data utilization. The
technical content of the discussionswas at a level sufficient to interest andbenefit experts in microwave radiome-try. As a result of the many positive re-sponses and the interest expressed inholding another workshop, the GRS-Scommunity can look forward to theSecond International Microwave Radi-ometer Calibration Workshop in ap-proximately two years.
For more information about the work-shop, photos, and abstracts of the presen-tations please visit our Web site,http://mitb.gsfc.nasa.gov/ucal.
Figure 2: Enjoying the lunch buffet at µCal. Pictured from left to right is: Janne Lahtinen, FredSolheim, Al Gasiewski, Roger Lang, Jim Wang, and Narinder Chauhan
Figure 3: Dr. Jim Shiue and Dr. Jim Randa lead the discussion on calibration standardsand references.
18 IEEE Geoscience and Remote Sensing Society Newsletter • March 2001
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IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 21
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IEEE Geoscience and Remote Sensing Society Newsletter • March 2001 23
Upcoming Conferences(continued from page 24)
Name: 16th International Conference on AppliedElectromagnetics and Communications
Dates: September 24-26, 2001Location: Dubrovnik, CroatiaContact: Davor Bonefacic
University of Zagreb, FERUnska 3, HR-10000 Zagreb, Croatia
Tel: +385.1.6129.727Fax: +385.1.6129.717Email: [email protected]: http://www.rasip.fer.hr/korema/icecom2001/
Name: Specialist Meeting on Microwave RemoteSensing
Dates: November 6-8, 2001Location: Boulder, ColoradoContact: Ed. R. Westwater, CIRES,
University of Colorado/NOAAEnvironmental Technology Laboratory325 Broadway MS R/E/ET1Boulder, CO 80305
Email: [email protected]: http://www.etl.noaa.gov/mrs01
(see pp. 20-21 for announcement)
Name: IEEE/ISPRS Joint Workshop on RemoteSensing and Data Fusion over UrbanAreas
Dates: November 8-9, 2001Location: Rome, ItalyContact: Paolo Gamba, Technical Chair
Department of Electronics, University of PaviaVia Ferrata, 1 27100 Pavia, [email protected]
Email: [email protected]: http://ele.unipv.it/urban_2001
FPO
UPCOMING CONFERENCES
The Institute of Electrical and Electronics Engineers, Inc.445 Hoes LaneP.O. Box 1331Piscataway, NJ 08855-1331
See also http://www.techexpo.com/events for more conference listings.
Name: International Workshop on Geo-SpatialKnowledge Processing for NaturalResource Management
Dates: June 28-29, 2001Location: University of Insubria, Varese (Italy)Contact: Elisabetta Binaghi, Institute for Multimedia
Information TechnologiesNational Research CouncilVia Ampere, 56Milan, I-20133 Italy
Tel: +39.02.70643287Fax: +39.02.70643292Email: [email protected]: http://proterra.itim.mi.cnr.it
Name: 5th WSES/IEEE World Multiconference OnCircuits, Systems, Communications &Computers (CSCC 2001)
Dates: July 8-15, 2001Location: Rethymnon, Crete (Greece)Email: [email protected]: http://www.softlab.ntua.gr/~mastor/cscc01.htm
Name: 2001 IEEE AP-S International Symposiumand USNC/URSI National Radio ScienceMeeting
Dates: July 8, 2001 - July 13, 2001Location: Boston, MAContact: Dr. Robert V. McGahan
Air Force Research Laboratory/SNH31 Grenier St.Hanscom AFB, MA 01731-3010
Tel: 781-377-2526Fax: 781-377-5040Email: [email protected]: http://ieeeaps.org/2001APSURSI
Name: First International Workshop on theAnalysis of Multi-temporal RemoteSensing Images (MultiTemp-2001)
Dates: September 13-14, 2001Location: Trento, ItalyContact: Lorenzo Bruzzone
MultiTemp 2001 Workshop SecretariatDICA - University of TrentoVia Mesiano, 77I-38050, Trento, ITALY
Tel: +39-0461-882623Fax: +39-0461-882672Email: [email protected]: http://www.multitemp.org
(see page 22 for announcement)
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