Contains table of contents for Section 4 and reports on six research projects.MIT Lincoln Laboratory Agreement BX-6178MIT Lincoln Laboratory Agreement BX-6433National Aeronautics and Space Administration/Goddard Space Flight Center Grant NAS5-31376MIT Lincoln Laboratory Agreement CX-19383National Aeronautics and Space Administration/Goddard Space Flight Center Grant NAG5-10MIT Leaders for Manufacturing Progra

Barrett, John W.

Blackwell, William J.

Burke, Bernard F.

Cabrera-Mercader, Carlos R.

Cao, Ronald

Hewitt, Jacqueline N.

Lee, Junehee

Rosenkranz, Philip W.

Schwartz, Michael J.

Staelin, David H.

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Section 4Chapter 1Radio AstronomyRadio Astronomy271272 RLE Progress Report Number 139Chapter 1. Radio AstronomyChapter 1. Radio AstronomyAcademic and Research StaffProfessor Bernard F. Burke, Professor David H. Staelin, Professor Jacqueline N. Hewitt, Dr. Philip W.Rosenkranz, John W. BarrettGraduate StudentsWilliam J. Blackwell, Carlos R. Cabrera-Mercader, Ron Cao, Junehee Lee, Michael J. SchwartzTechnical and Support StaffFelicia G. Brady, Anne E. Conklin1.1 Algorithms for OperationalMeteorological Satellite InstrumentsSponsorMIT Lincoln LaboratoryAgreement BX-6178Project StaffDr. Philip W. Rosenkranz, Carlos R. Cabrera-Mercader, Michael J. SchwartzThis project provides scientific support to theNational Oceanic and Atmospheric Administration(NOAA) for the advanced microwave sounding unitsA and B (AMSU-A, AMSU-B), which are scheduledfor launch on NOAA polar-orbiting weather satellitesstarting in 1997, and also for improved instruments.The effort emphasizes development of atmospherictransmittance algorithms, estimation of surfaceemissivity and precipitation, issues related to instru-ment design and specification, and general retrievalmethods.1.2 Development and Operation of anNPOESS Aircraft Sounder TestbedPassive Microwave SensorSponsorMIT Lincoln LaboratoryAgreement BX-6433Project StaffDr. Philip W. Rosenkranz, John W. Barrett, WilliamJ. BlackwellThe NPOESS Aircraft Sounder Testbed (NAST) is acooperative effort by MIT Lincoln Laboratory, RLE,and the University of Wisconsin. An infrared inter-ferometer sounder and a co-located microwavesounder will be flown on the NASA ER-2 aircraft forthe purpose of answering technical questionsrelated to the National Polar-orbiting OperationalEnvironmental Satellite System (NPOESS). Themicrowave sounder will be an improved version ofthe microwave temperature sounder (MTS) whichhas been flown previously by RLE. The new MTSwill have eight channels between 50 and 56 GHzand nine channels near 119 GHz. It will be fullyscanning and will have a three-point calibrationsystem (two blackbody targets and a zenith view)for accurate calibration.1.3 Earth Observing System: AdvancedMicrowave Sounding UnitSponsorNational Aeronautics and Space Administration/Goddard Space Flight CenterGrant NAS5-31376Project StaffProfessor David H. Staelin, Dr. Philip W.Rosenkranz, John W. Barrett, William J. Blackwell,Carlos R. Cabrera-MercaderThe AMSU will provide microwave-band measure-ments to the atmospheric infrared sounder (AIRS),which will be a facility instrument on NASA'splanned Earth observing system (EOS). This effortis directed toward developing algorithms for theretrieval of temperature and humidity profiles, pre-cipitation, sea ice, land snow cover, and otherparameters. The temperature and humidity profiles273Chapter 1. Radio Astronomyobtained from AMSU are intended to provide initialconditions for the AIRS infrared cloud-correctionand profile retrieval algorithms.Data from present satellite instruments with lowerspatial resolution were used to test the microwavealgorithms. The humidity retrievals show spatialpatterns that are sufficiently distinct at different alti-tudes to demonstrate vertical resolution, although aquantitative measure of vertical resolution has notbeen defined.Methods of combining AIRS and AMSU measure-ments in an optimum cloud-clearing algorithm werestudied. Our approach is to estimate the impact ofclouds on the temperature retrieval at each of nineAIRS locations associated with one AMSU-A loca-tion. Then, this information is then input to a neuralnetwork that estimates the temperature profile as anonlinearly weighted average over the nine loca-tions.An information-conserving data compressionmethod was developed for application to high-data-rate atmospheric sounders. It compresses the geo-physical component of the data in a non-deleteriousway by noise-adjusted principal components anal-ysis and codes losslessly any instrument channelsexhibiting anomalies greater than three standarddeviations above the noise level. This method,described as semi-lossless, has the robustness oflossless coding, but can approach the high-compression performance of lossy coding.1.3.1 PublicationsBlackwell, W.J., and D.H. Staelin. "Simulation Ana-lyses of the Integrated Multispectral AtmosphericSounder (IMAS) for Tropospheric Sounding ofTemperature and Water Vapor Profiles." Paperpresented at the Fifth Specialist Meeting onMicrowave Radiometry and Remote Sensing ofthe Environment, Boston, Massachusetts, Nov-ember 4-6, 1996.Rosenkranz, P.W. "Retrieval of Atmospheric Mois-ture Profiles from SSM/T2 Measurements."Paper presented at the Fifth Specialist Meetingon Microwave Radiometry and Remote Sensingof the Environment, Boston, Massachusetts,November 4-6, 1996.Schwartz, M.J., P.W. Rosenkranz, and D.H. Staelin,"Atmospheric Transmittance MeasurementsNear 118-GHz." Proceedings of the SPIE Con-ference GOES-8 and Beyond, Denver,Colorado, August 7-9, 1996.1.4 Geostationary Microwave SounderStudySponsorMIT Lincoln LaboratoryAgreement CX-19383Project StaffDr. Philip W. Rosenkranz,J. BlackwellJohn W. Barrett, WilliamThis project provides supporting studies of candi-date sounder designs to the GeosynchronousMicrowave Sounder Working Group (GMSWG),which is composed of government and universitypersonnel. GMSWG was formed at the order ofNOAA for the purpose of identifying requirements,determining technology readiness, and makingrecommendations for a microwave sounder to beadded to the Geostationary Operational Environ-mental Satellite (GOES) program.GMSWG, chaired by Professor Staelin, has devel-oped a reference sounder design that envisions a 2m-diameter antenna and four frequency bands,which include the oxygen lines at 119 and 425 GHzand the water lines at 183 and 380 GHz. Simu-lations of temperature and humidity retrievals fromthis instrument predict accuracies comparable tolow-earth-orbit sounders, except that the 425 and380 GHz bands are limited by continuum water-vapor absorption to parts of the atmosphere withwater-vapor overburden less than 0.3-0.6 kg/m 2.The 119 and 183 GHz bands, in contrast, allowsounding down to the surface. Subsatellite hori-zontal spatial resolution would be -20 km for the380-425 GHz bands, however, compared with -66km at 119 GHz.1.5 High-Resolution Passive MicrowaveImaging of Atmospheric StructureSponsorNational Aeronautics and Space Administration/Goddard Space Flight CenterGrant NAG5-10Project StaffProfessor David H. Staelin, John W. Barrett, Dr.Philip W. Rosenkranz, Michael J. Schwartz274 RLE Progress Report Number 139Chapter 1. Radio AstronomyA zenith-scanning airborne imaging spectrometer,the Microwave Temperature Sounder (MTS), incor-porating eight double-sideband channels centeredon the 118.75-GHz oxygen resonance, wasemployed to measure atmospheric transmittance tospace. The MTS channels have nominal single-sideband widths of 270 MHz and center frequenciesof 470-1880 MHz from the line center. Observa-tions were obtained continuously as a NASA ER-2aircraft ascended to -20 km altitude anddescended on four flights. Nearby radiosondes andnavigational and air temperature data from the air-craft permit comparison of the radiometric measure-ments with predictions of microwave transmittancemodels. The views of atmospheric radiance againstthe cosmic background provide sensitivity to condi-tions in the troposphere including the tropopauseregion. Modeled and retrieved atmosphericopacities presently agree to within the accuracy ofthe measurements, which is typically -5 percentthrough altitudes from 5 to 15 km. Analysis of datafrom an associated switched-frequency radiometeroperating 52-54 GHz as part of MTS is also beinganalyzed. Work began on designing improvementsto the ER-2 aircraft instrument which will addressissues of calibration accuracy, frequency coverage,and the ability to scan laterally to produce imagesin the 50-57 GHz region.1.6 Reduction of VariationSponsorMIT Leaders for Manufacturing ProgramProject StaffProfessor David H. Staelin, Ron Cao, Junehee LeeReduction of process and product variation is aprimary goal in most manufacturing operations.Progress this year has centered on data mining ofdata-rich web manufacturing processes. Two verydifferent web processes are being analyzed. Ineach case, hundreds or thousands of parametersare being monitored continuously. Genericmethods are being developed for characterizingmodes of behavior of complex nonlinear processesand identifying anomalies.275276 RLE Progress Report Number 139

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