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Dr. Fred Aminzadeh

Unocal, Houston

Contact Information:

Dr. Fred Aminzadeh
Seismic Methods and Applications
14141 Southwest Freeway Sugarland, TX 77487-3435
USA
Tel.: 713-287-5947
Fax:
E-mail: stgpfam@st.unocal.com

Talk Abstract: Soft Computing and Its Impact on Geoscience Applications

What is soft computing? Soft computing (SC)--unlike traditional, hard computing (HC)--is tolerant of imprecision, uncertainty and partial truth. Thus the guiding principle of soft computing is: Exploit the tolerance for imprecision, uncertainty and partial truth to achieve tractability, robustness and low solution cost. Underlying this principle is an obvious and yet frequently neglected fact that precision carries a cost. What this implies is that to achieve a low cost--or to be able to solve a problem--it is necessary to aim at a solution which is precise enough but no more than necessary. The same applies to uncertainty and partial truth.

Principal constituents of Soft Computing (SC) are Fuzzy logic (FL) neural networks (NN) and probabilistic reasoning (PR). PR itself includes belief networks, genetic algorithms, chaos theory and learning theory. In the triumvirate of SC, FL is concerned in the main with imprecision, NN with learning and PR with uncertainty. In large measure, FL, NN and PR are complementary rather than competitive. Indeed, what is becoming increasingly clear is that in many cases it is advantageous to employ FL, NN and PR in combination rather than exclusively. In particular, the combination of FL and NN leads to so-called neurofuzzy systems which are rapidly gaining in visibility.

Soft computing has already found its way to many geophysical applications. These include both exploration geophysics and earthquake seismology. Both of these categories of applications happen to be logical domain for various aspects of SC.

The major application areas include:

These applications and the value and relevance of different aspects of SC will be highlighted.

Applications of Seismic Imaging and Generalized Kalman Filtering in the Processing and Analysis of the SAR Data

The main objective of this presentation is to demonstrate application of the imaging technology developed for seismic data processing to SAR data. This will enhance the resolution while reducing the computation time and cost for SAR data processing. It will be feasible to perform real data processing and data analysis with major technical and commercial impact.

Conventional SAR data focusing techniques of match filtering and convolution with range variant phase signal is very expensive and the resolution is not adequate for many practical and commercial applications. This is due to the fact that most of the current algorithms used are space variant requiring very time consuming implementations.

Recent advances in seismic exploration, has made it possible to process large volumes of data. Imaging methods of petroleum exploration have been evolving during the last two decades. Their main thrust are to account and correct for the defocusing of acoustic waves propagating through the subsurface. Similarly, ( albeit not as severely) the propagation of the electromagnetic waves through the atmosphere also results in a nonlinear ray path. The straight line ray path assumption of the conventional processing of SAR data, in conjunction with the monochromatic assumption of the conventional interferometry leads to significant loss of resolution.

This problem has been recognized several years ago and some solutions have been offered. Dramatic changes on the way SAR data is processed and analyzed is envisioned by the introduction of novel seismic migration techniques to SAR data. This method will use a very fast seismic migration algorithm combined with the generalized Kalman Filtering (GKF) approach. GKF has been successfully used for sonar applications with multiple sensors to maximize resolution while accounting for phase shifts and time delays of different sensors. Better accuracy and improvement in generating and analyzing interfergrams is expected. The long term benefits of these new developments are their potential impact on the planned LightSAR. It will help facilitate accomplishing its mission of much improved resolution and real time processing.

Dr. Wolfgang-Martin Boerner

Professor of Electrical Engineering and Computer Science, The University of Illinois at Chicago

Contact Information:

Permanent Address:

Dr. Wolfgang-Martin Boerner
UIC-EECS/CSN, m/c 154
851 S. Morgan St., SEO-1120
Chicago, IL 60607-7053
USA
Tel.: 312-996-5480 (O) 708-498-4457 (H)
Fax:
E-mail: boerner@parsys.eecs.uic.edu


Talk Abstract: WISIP, Wideband Interferometric Sensing and Imaging Polarimetry

`WISIP' has become an indispensable tool in wide area environmental surveillance of the terrestrial and planetary covers. It allows dynamic optimal image feature extraction of significant characteristics of desirable target and/or target sections with simultaneous suppression of undesirable background clutter/speckle at hitherto unknown clarity and of never achieved quality. `WISIP' may be adapted to the Detection, Recognition, and Identification (DRI) of any stationary, moving, or vibrating target or distributed scatterer segment versus arbitrary stationary, dynamically changing or moving geophysical/ecological environments. For example, the DRI of stealthy dynamically moving or camouflaged stationary objects occluded in heterogeneous stationary and/or dynamically moving background clutter such as precipitation scatter, the ocean surface boundary layer, the littoral coastal surf zone, pack-ice and show or vegetative canopies, etc., can now be successfully realized.

A succint review of the pertinent polarimetric theory, metrology, and systems calibration, sensor design and technology as well as a vector signal and tensor image processing is presented together with a comprehensive overview on how these modern high resolution/interferometric precision, complete polarimetric co-registered signature sensing and TOPological InterFerometric (TOPIF) POLarization Synthetic Aperture Radar (POL-SAR) imaging techniques, complemented by full integration of novel navigational electronic tools such as GPS-INU, will advance electromagnetic vector wave sensing and imaging towards the limits of physical realizability. Various examples of wideband polarimetric image interferometry are presented including: (i) co-seismogenic/volcanologic 3-axis ULF/ELF electro/magneto-metric signature analyses in low frequency polarimetry; (ii) Beyond-the-Horizon POL-RAD Imaging and Inverse Scatterometry in HV/VHF Polarimetry; (iii) Polarimetric Radar Meteorology in Ground-based SHF (1-30GHz) Doppler Polarimetry; (iv) Air/Space-borne Ultra-wideband (10MHz-100GHz) TOPological InterFerometric (TOPIF) POLarimetric Synthetic Aperture Radar (POL-SAR) imaging implementing both CATI (Cross/Along-Track Inflight) and Repeat-Track/Orbit LTBL (Long Temporal BaseLine) interferometry utilizing the airborne NASA-JPL-AIRSAR and the NAWC-ERIM-P3-Quadband TOPIF-POLSAR platforms, the spaceborne shuttle SIR-C/X-SAR TOPIF-POLSAR and the satellite ERS-1 and JERS-1 TOPIF-SAR systems; (v) Recently advanced POL-IR imagers; as well as (vi) Polarimetric mult-spectral NIR-OPT-NUV and UV spaceborne imagers.

The lecture is concluded with a succinct critical analysis on still unresolved major problems encountered in perfecting `WISIP' as well as a preview on anticipated near-future TOPIF-POLSAR imaging systems advances and how with its extra-wideband implementation in wide area environmental monitoring and military surveillance mankind may come a step closer in fully realizing the "irreversible paradigm conversion from military nationalist toward environmental global defense".

(90 minutes plus a 30 minute video)

Talk Abstract: DIMRP, Direct and Inverse Methods in Radar Polarimetry

DIMRP - in support of developing high resolution vector (polarization) electromagnetic sensing and imaging techniques (60 minutes).

A full abstract will be available at a later date.

Dr. Weng Cho Chew

Professor of Electrical and Computer Engineering, University of Illinois

Contact Information:

Dr. Weng Cho Chew
Electromagnetics Laboratory
Department of Electrical and Computer Engineering
University of Illinois
1406, West Green Street
Urbana, IL 61801
USA
Tel.:
Fax:
E-mail: chew@cspark.ece.uiuc.edu

Talk Abstract: Fast Algorithm, Inverse Scattering and Their Applications to Remote Sensing Problems

In this talk, we will discuss several efficient method of solving scattering problems by inhomogeneous bodies. These methods include recursive method called the recursive aggregate T matrix method (RATMA), the nested equivalence principle algorithm (NEPAL), and the CG-FFT type iterative methods. The strength of each method will be discussed, and compared to other existing methods. Then illustration of the use of these methods to solve the inverse scattering problem is described. The inverse scattering problem is solved with the Born iterative method, the distorted Born iterative method, and the local shape function method. The use of these inverse algorithms on experimental data of both the microwave type, as well as ultrasonic data will be illustrated.

Prof. B. L. Deekshatulu

Director, National Remote Sensing Agency, Hyderabad, India

Contact Information:

Prof. B. L. Deekshatulu
Director, National Remote Sensing Agency
Department of Space
Goverment of India
Hyderabad - 500 037
INDIA
Tel.: 0091-040-278360 (direct) or 0091-040-279572 ext. 2320
Fax: 0091-040-277210
E-mail: bld%nrsa-hyd@uunet.in

Talk Abstract: Indian Remote Sensing Programme for Resource Management

India, realising the importance of Eye in the Sky, for resource monitoring and management has initiated its Remote Sensing Programme way-back in 1960's. Since then, it has crossed many major milestones, beginning with conducting of Aerial Surveys using variety of sensors for monitoring crops; building and launching of Bhaskara I & II experimental Remote Sensing Satellites in the time frame of 1975-82, paving the way for conceptualisation and implementation of a space platform, ground based data reception and processing, data interpretation and utilisation etc.

As a next step in the operational space based remote sensing programme, indigenously developed state-of-the-art first generation Indian Remote Sensing Satellites IRS 1A & IRS 1B were launched in 1988 and 1991 respectively; IRS P2 in 1994 using indigenously developed PSLV D2 along with a compatible ground segment to receive the data, generate data products and disseminate them to the users.

Usage of remote sensing technology for various resources monitoring has not only been tested and demonstrated, but is also being routinely applied in an operational way. In order to proliferate this high technology in the development projects of various resource sector departments, National Natural Resources Management System (NNRMS) and Natural Resources Information Systems (NRIS) have been set-up with the establishment and functioning of Remote Sensing State Centres and Regional Centres. The importance of training of scientists of various user organisations in the use of this technology has also been realised and a Training Centre of international repute has been established, where about 2700 personnel have been trained so far.

The various aspects of the Indian Remote Sensing Programme and the achievements thereof will be discussed.

Talk Abstract: Geosphere Biosphere Studies in India - Remote Sensing Applications

International Geosphere Biosphere Programme (IGBP) of International Council of Scientific Unions has overall objective of describing and understanding the interactive physical, chemical and biological processes that regulate the total earth system, the unique environment it provides for life, the changes that are occuring in this system and the manner in which they are influenced by human actions. The population explosion and the advent of new technological developments have become the cause of environmental impacts that are global in nature. Increasing concentration of greenhouse gases in the atmosphere due to burning of fossil fuels, changes in agricultural practices, deforestation, industrialisation, waste disposal, urbanisation, landuse patterns are contributing to changes in terrestrial and coastal ecosystems and have impacts on productivity, water resources and ultimately on the atmosphere. India, with its diverse environmental conditions and ecosystems and with economy closely linked with the monsoon performance, has several problems which need to be addressed. The problems include drought/desertification, floods, deforestation, pest infestation, land degradation etc. These are closely linked with the weather and the climatic changes on one hand and the environmental and ecological effects and interaction on the other. Remote sensing technology provides a valuable tool for monitoring various natural resources on global and synoptic scale. In India, several projects related to core themes of IGBP like IGAC, JGOFS, LOICZ, GCTE, GAIM, PAGES, etc. have been carried out using remote sensing data and extensive ground measurements. The methane emission studies from rice paddy fields in India suggested that the emission rates are considerably lower than the figure projected. The results of various studies under this programme in India will be presented.

Dr. Richard J. Doviak

Senior Engineer, National Severe Storms Laboratory, and Professor of Meteorology and Electrical Engineering, University of Oklahoma

Contact Information:

Dr. Richard J. Doviak
National Severe Storms Laboratory
1313 Halley Circle
Norman, OK 73069
USA
Tel.: 405-366-0401
Fax: 405-366-0472
E-mail: doviak@nssl.uoknor.edu

Talk Abstract: Doppler Radar and Weather Observations

To be able to observe remotely internal motions of tornadic thunderstorms is an impressive experience. This speaker has had the good fortune to be part of a group of engineers and atmospheric scientists involved in developing a Doppler weather radar to probe the internal structure of wind and precipitation inside severe storms, as well as in the storm's antecedent environment. This research and development will lead to improvements in the short term prediction and warnings of hazardous weather. The Doppler weather radar techniques which were developed at the National Severe Storms Laboratory have found application in the networks of Doppler radars presently being deployed by various nations and, in particular, the USA National Weather Service's network (NEXRAD). Similar Doppler radars are also being deployed around airports to detect wind shears hazardous to safe flight.

This colloquium will highlight the theory of Doppler radar, signal processing, and the research conducted at this laboratory to show the structure of many of the weather phenomena (tornadoes, solitary waves, microbursts, etc.) made evident by the Doppler weather radar. To relate radar observations to weather events commonly observed by eye, radar data fields are correlated with photographs of the phenomena. Wind shear hazards to aviation will also be presented. Most of the topics to be presented are found in the textbook "Doppler radar and weather observations," 2nd edition (1993), published by Academic Press.

Emphasis on any of these topics (i.e., Doppler weather radar theory, signal processing, meteorological interpretation, operational applications, aviation weather hazards, and wind and temperature profiling) can be adjusted to match the interest of the members of the chapter.

Dr. Anthony W. England

Radiation Laboratory, University of Michigan

Contact Information:

Dr. Anthony W. England
Radiation Laboratory
University of Michigan
Ann Arbor, MI 48109-2122
USA
Tel.: 313-936-1340
Fax: 313-747-2106
E-mail: england@eecs.umich.edu

Talk Abstract: Radiobrightness as an Aid to Weather and Climate Prediction

Weaknesses in the Soil-Vegetation-Atmosphere Transfer (SVAT) models that are used to estimate energy, moisture, and momentum fluxes at the land-atmosphere boundary significantly limit the reliability of numerical weather prediction and of short-term climate prediction for continental landmasses. Biophysical processes associated with evapotranspiration are so complex that errors accumulate in estimates of stored water and leaf temperature and, consequently, of latent energy flux.

An alternative to complete reliance upon the veracity of a propagating SVAT model is to correct current moisture content and temperature through remote sensing observations. We are attempting to use the strong dependence of radiobrightness upon the moisture content and temperature of vegetation and soil to detect errors in SVAT estimates of these parameters. We anticipate that differences between observed and predicted brightnesses can be also used to correct the model. This hypothesis is being tested for prairie grassland and for arctic tundra because these are extensive regions that are relatively homogeneous over the relatively large footprints of the 19.35, 22.235, 37.0, and 85.5 GHz Special Sensor Microwave/Imager (SSM/I) radiometers flying on several of the Defense Meteorological Satellites.

I will describe our progress with coupled SVAT/Radiobrightness models, our field experiments in South Dakota and on the Arctic Slope of Alaska, and our interpolation and atmospheric correction schemes for SSM/I data.

Dr. Adrian K. Fung

Wave Scattering Research Center, University of Texas at Arlington

Contact Information:

Dr. Adrian K. Fung
Wave Scattering Research Center
Electrical Engineering Department
University of Texas at Arlington
UTA Box 19016
Arlington, TX 76019
USA
Tel.: 817-273-3422
Fax: 817-273-3443
E-mail: eefung@uta.edu

Talk Abstract: Radar Scattering Models for Soil and Sea Surfaces

The problem of EM wave scattering from irregular surfaces was of interest in the late 1950's in radar exploration of planetary surfaces and more recently in the study of the Earth surfaces. Before the 1970's the available surface scattering models were restricted to roughness either small or large compared with the incident wavelength. Over the last twenty years many methods were proposed to extend the validity of surface scattering model to cover the intermediate frequency range. In this study one such surface scattering model (known as the integral equation model, (IEM)) is presented. This surface scattering model is based on an approximate solution of the integral equation for the surface current density without assuming low or high frequency conditions. This is the reason why it is not restricted to either high or low frequency region.

We shall first show that the surface scattering model is indeed valid over the entire frequency axis by noting that it reduces analytically to well known low and high frequency models. Then, we show that it compares well with controlled laboratory measurements from statistically known surfaces characterized by a known rms height and correlation function over a wide frequency range including the intermediate frequency region.

Next, we show its applicability to scattering from the soil surface by relating first the dielectric constant within the model to soil moisture, frequency and soil texture. The field measurements considered include two soil surfaces with rms heights of 0.4 cm and 1.12 cm and correlation lengths of 8.4 cm and 8.45 cm respectively. The measurement frequencies are 1.5, 4.75 and 9.5 GHz. The angular range is from 10 to 70 degrees and both VV and HH polarizations are considered.

Finally, we consider its applicability to scattering from ocean surfaces. Due to the presence of wind fields over the ocean, the sea surface is a skewed surface. Thus, in addition to surface rms height and correlation function, the third order statistics represented by the bispectrum of the sea surface has to be included in modeling. It is shown that good agreements are realized over both the polar and azimuthal angles indicating how radar scattering varies with the direction of the wind.

Dr. Samuel D. Gasster

Microwave Remote Sensing Radar & Signal Systems Dept., The Aerospace Corporation

Contact Information:

Dr. Samuel D. Gasster
Senior Engineering Specialist
Microwave Remote Sensing
Radar & Signal Systems Department
The Aerospace Corporation
M4-927
P. O. Box 92957
Los Angeles, CA 90009-2957
USA
Tel.: 310-336-6005
Fax:
E-mail: gasster@courier6.aero.org

Talk Abstract: Spaceborne Microwave Radiometry of the Earth: Principles, Systems and Applications

During the last 20 years the passive microwave remote sensing of the earth from space has become an important research and operational tool. The use of microwave radiometers for measurements of the earth surface and atmosphere has reached a significant level of maturity. Systems have been flown as part of specialized research satellites and as part of operational systems. This talk will review the developments in spaceborne passive microwave remote sensing over the last 20 years, and discuss some of the systems and trends for the future. Starting with a survey of the missions flown to date, I will then discuss the basic principles which allow one to perform remote sensing measurements using microwave radiometers and sounders. Microwave thermal emission phenomenology will be examined along with some of the measured characteristics of the earths surface (land and oceans) and atmosphere. The radiative transfer equation will be discussed and examples of how it relates to the measurement of surface and atmospheric parameters will be demonstrated. The system design and operating principles of microwave radiometers and sounders will be summarized using examples from past, present and future systems. The retrieval of geophysical parameters from microwave remote sensing data is a key aspect of the utility of microwave radiometer systems. The basic concepts of retrieval techniques will be discussed and examples of retrieving ocean surface wind speed and direction, sea ice parameters, rain rate and atmospheric temperature and humidity profiles will be given. Data examples from various systems (SMMR, SSM/I, SSM/T1, SSM/T2, Topex MW Radiometer) will be given. Finally, I will conclude with a look at future developments, such as passive microwave polarimetry, that are presently being explored. A brief status report on the converged weather satellite program, the National Polar-Orbiting Operational Environmental Satellite System (NPOESS), will be given.

Dr. David G. Goodenough

Advanced Forest Technologies Program, Natural Resources Canada

Contact Information:

Dr. David G. Goodenough
Advanced Forest Technologies Program
Natural Resources Canada
506 West Burnside Road
Victoria, B.C. V8Z 1M5
CANADA
Tel.: 604-363-0776
Fax: 604-363-0775
E-mail: dgoodenough@a1.pfc.forestry.ca

Talk Abstract: Intelligent Integration of Remote Sensing and Geographic Information

In order to monitor the land resources of the planet, it is necessary to use remote sensing from multiple sensors and integrate these data with historical information contained within geographical information systems (GIS). Multiple sensors are required to identify attributes of interest. In forestry, resource managers want to know the amount of the resource by species, area, timber volume, etc., the spatial distribution, and the temporal changes of the resource, both past and predicted for the future. The technologies of the IEEE Geoscience and Remote Sensing Society are used to create information systems to support land management. In this presentation we describe an intelligent system which integrates remote sensing from aircraft and satellites with GIS. This system uses case-based reasoning and expert systems to capture knowledge from humans expert in several disciplines and to learn from each analysis. Models of forest growth over time are used to predict future forest cover and the results are visualized dynamically. Integration of remote sensing and GIS also requires high speed communication between several resource agencies. An ATM network operating at 155 Mb/s is used to facilitate the rapid movement of GIS and remote sensing data, and digital collaboration with distant experts.

Professor Martti Hallikainen

Laboratory of Space Technology, Helsinki University of Technology

Prof. Martti T. Hallikainen
Helsinki University of Technology
Laboratory of Space Technology
Otakaari 5A FIN-02150 Espoo
FINLAND
Tel.: 358-9-451-2371
Fax: 358-9-451-2898
E-mail: Hallikainen@hut.fi

Talk Abstract: Microwave Remote Sensing in Europe

Recent development of microwave remote sensing in Europe has been rapid both in technology and in applications. Europe's first remote sensing satellite ERS-1 has provided scientists with SAR scenes, AMI wind mode and wave mode data, and altimeter data. The ERS-2 satellite was launched in 1995, and the next two satellites, ENVISAT-1 (launch in 1999) and METOP (launch in 2000), are under construction. For the development of applications, numerous ERS-1/2 Announcement of Opportunity and Pilot Projects are in progress, and data has been obtained from the first tandem flight of two spaceborne SAR sensors. Recent ESA initiatives include the Earth Explorer (application development) and Earth Watch (operational remote sensing) programs.

Advanced spaceborne sensors are under development by ESA, including the ASAR synthetic aperture radar (C-band, VV polarization, swath width 500 km) and RA-2 radar altimeter Ku-band and S-band). Development of the MIMR microwave radiometer (dual-polarized, 6 to 89 GHz) has been temporarily halted, because the sensor could not be accommodated onboard near-future satellites.

Airborne SAR sensors have been constructed in several countries, including Germany (ESAR), Denmark (EMISAR), The Netherlands (PHARE) and France. Airborne scatterometers have been built in the Netherlands, France, Finland and Germany. Airborne MIMR simulators for application development are available in Finland and France.

The role of the European Union in remote sensing is increasing. The European Microwave Signature Laboratory (EMSL) is used to study the basic scattering behavior of various targets and to develop methods for interpretation of satellite data. The Centre for Earth Observation (CEO) is a European Commission funded program for advancing the use of Earth observation data. Numerous EU-funded research projects are in progress; the project teams consist of remote sensing institutes and companies in various EU member countries and other participating countries.

The main research topics in microwave remote sensing in Europe include ocean, sea ice, forests, agriculture, snow, atmosphere and environmental monitoring. Ocean-related studies are conducted mainly in Atlantic and Mediterranean countries. Sea ice studies are in progress concerning the Greenland Sea, Norwegian Sea and Baltic Sea. In forestry, topics ranging from boreal to tropical forests are under study. Application of ERS-1/2 SAR data to the inventory of forests is an important topic. Radiometer and radar studies of snow are conducted both in Scandinavia and in the Alpine region.

In some areas, remote sensing activities in Eastern European countries have reached a high standard. For example, determination of soil moisture from radiometer data has been investigated extensively in Russia, Hungary and Bulgaria. International programs have been established to foster cooperation between East and West.

Dr. Haralambos N. Kritikos

Professor of Electrical Engineering, University of Pennsylvania

Contact Information:

Dr. Haralambos N. Kritikos
Department of Electrical Engineering
University of Pennsylvania
200 S. 33 Str.
Philadelphia, PA 19104
USA
Tel: 215-898-8112
Fax: 215-573-2068
E-mail: kritikos@ee.upenn.edu

Talk Abstract: Scattering from Natural Surfaces. Time Frequency Windows.

Abstract available at a later date.

Dr. David Landgrebe

Professor of Electrical Engineering, Purdue University

Contact Information:

Dr. David Landgrebe
Department of Electrical and Computer Engineering
Purdue University
West Lafayette, IN 47907-1285
USA
Tel: 765-494-3486
Fax: 765-494-3358
E-mail: landgreb@ecn.purdue.edu

Talk Abstract: Methods for the Analysis of Hyperspectral Remote Sensing Image Data

There are a substantial number of sensor system now coming into use around the world which generate image data in several 10's to several hundreds of spectral bands at once. Analysis procedures for such data have been the subject of a focused research program for the last decade. In this presentation we will begin by examining aspects of such hyperspectral data that have been found to be unique. We will next describe some useful tools for analysis of such data. These include

The presentation will conclude with an example analysis of a hyperspectral data set using these methods. A web site on this topic contains extensive references and a downloadable software package for personal computers that allow evaluation of some of the algorithms and procedures described. The URL for the web site is http://dynamo.ecn.purdue.edu/~biehl/MultiSpec/.

Dr. David M. Le Vine

Microwave Sensors Branch, NASA/Goddard Space Flight Center

Contact Information:

Dr. David M. Le Vine
Mail Code 975
NASA/Goddard Space Flight Center
Greenbelt, MD 20771
USA
Tel: 301-286-8059
Fax: 301-286-0294
E-mail: dmlevine@meneg.gsfc.nasa.gov

Talk Abstract: Aperture Synthesis for Passive Microwave Remote Sensing of the Environment from Space

Passive remote sensing in the microwave portion of the spectrum can provide measurements of many parameters important for understanding the earth environment (e.g. soil moisture, sea surface temperature, profiles of atmospheric temperature and water vapor, etc.). However, realizing the full potential of passive microwave remote sensing from space requires large antenna apertures in orbit. This is especially a problem for measurements made at the low end of the microwave spectrum (e.g. soil moisture and sea surface salinity) where the wavelength is very long.

Aperture synthesis is a new technique for passive remote sensing (i.e. radiometers as opposed to radars) being developed to help overcome this problem. Aperture synthesis is an interferometric technique in which the correlation between pairs of small antennas and signal processing is used to achieve the resolution of a single large antenna. An aircraft prototype called, ESTAR, has been built to develop the technique. Instrument development and validation is part of collaborative research involving partners at NASA's Goddard Space Flight Center, the University of Massachusetts and the USDA's Agricultural Research Service.

This talk will give a brief introduction to passive microwave remote sensing and explain the concept of aperture synthesis. The prototype instrument, ESTAR, will be described and example measurements presented. (ESTAR is an L-band radiometer which has been used to make measurements of soil moisture and ocean salinity.) The talk will conclude with some concepts currently under consideration for deployment of a synthetic aperture radiometer in space.

Talk Abstract: Lightning from a Remote Sensing Perspective

Lightning is a strong radiator of electromagnetic energy over a large portion of the RF spectrum. The radio static one hears during a thunderstorm is an example. A surprise of modern day research is that many of the pulse in this "noise" have characteristic shapes which can be associated with the lightning physics. This discovery has been used to develop instrumentation to locate lightning strike points and has the potential as a remote sensing tool to offer insight into the physics of the discharge.

This talk has two parts. In the first part, an elementary review will be given of the physics of the lightning discharge. The focus will be on what people usually see (i.e. cloud-to-ground flashes) and the electromagnetic characteristics of these events will also be described. Then, results will be presented from the speakers research using simple antenna theory to model these events and use them to understand such things as the evolution of current as it propagates along the lightning channel.

Dr. Robert E. McIntosh

Department of Electrical and Computer Engineering, University of Massachusetts at Amherst

Contact Information:

Dr. Robert E. McIntosh
Dept. of Electrical and Computer Engineering
University of Massachusetts
Amherst, MA 01003
USA
Tel: 413-545-0779
Fax: 413-545-4652
E-mail: mcintosh@ecs.umass.edu

Talk Abstract: Millimeter-wave Polarimetric Measurement Systems for Atmospheric and Terrestrial Remote Sensing

The Microwave Remote Sensing Laboratory of the University of Massachusetts has recently developed several polarimetric radars for remote sensing of natural surfaces and atmospheric phenomena at 35,95 and 225 GHz. These instruments, also known as polarimeters, have been used in a variety of measurement programs including studies of the backscattering characteristics of foliage, terrain, and snowcover at 35, 95 and 225 GHz and detailed measurements of the polarimetric behavior of clouds and precipitation at 95 GHz. We developed a 33/95 GHz polarimetric Cloud Profiling Radar System (CPRS), which maps reflectivity, velocity, and depolarization in clouds and precipitation. We are now developing a 95 GHz airborne radar with JPL and are designing a solid-state 95 GHz system to fly on an unmanned airborne vehicle (UAV) platform for the DOE. Most of these instruments are capable of measuring the target Mueller matrix, using either coherent or noncoherent techniques. This general talk will discuss the design of a number of novel millimeter wave radar systems, and experimental results obtained with them.

Talk Abstract: Digital Beam Forming Systems for Ocean and Atmospheric Remote Sensing

The Microwave Remote Sensing Laboratory has developed a digital beam forming system that provides high resolution images of the ocean surface. This Focused Phased Array Imaging Radar (FOPAIR) system is capable of obtaining images having 1m^2 pixel size in a one millisecond time period. This system is capable of obtaining wave spectrum measurements when the radar antenna pointing direction is close to grazing. MIRSL has also developed a beam forming wind profiling system for research of atmospheric boundary layer turbulence. This 915 MHz system is comprised of a single transmitting antenna and 91 receiving antennas and is called the Turbulent Eddy Profiler (TEP). The talk will describe the engineering details of FOPAIR and TEP and will contain experimental data, which show the advantages of beam forming in modern remote sensing applications.

Dr. Richard K. Moore

Professor Emeritus, EECS, University of Kansas

Contact Information:

Dr. Richard. K. Moore
Radar Systems and Remote Sensing Laboratory
2291 Irving Hill Road
Lawrence, KS 66045-2969
USA
Tel: 913-864-4836 (O) 913-843-3697 (H)
Fax: 913-864-7789 (O) 913-864-8207 (H - must be proceded by phone call)
E-mail: rmoore@eecs.ukans.edu (also Compuserve 74106,73)

Talk Abstract: Microwave Remote Sensing from its Beginning to its Current State of the Art

Microwave remote sensing for civilian purposes started in the early 1960s. Before tracing the history of microwave remote sensing, we examine the reasons we use microwaves for observing the earth. We then trace the history of the field, including signature studies, use of imaging radars, systems development and space radars.

After discussing the nature of a radar remote-sensing system, we trace the development of radar sensing of oceans, vegetation, geology, and sea ice. This is followed by a brief discussion of system-development history. This leads to an assessment of the current state of knowledge in each area, and of unsolved problems that we can see today.

We conclude with some ideas on the philosophy and ultimate goals of microwave remote sensing. Finally, some suggestions follow on the future of spaceborne remote sensing.

Talk Abstract: What? No Clouds? Radar Observation of the Earth

You need aerial or space photographs of an area, but it is cloudy or dark. What can you do? You can use an imaging radar. It can look through clouds and rain and make a picture similar to a photograph. Moreover, radar is more sensitive to soil and plant moisture than optical sensors. Radar also penetrates thin vegetation and a little soil, so the pictures are some different, but give extra information not in photos. Thus, when both can be used together, they are complementary just as having more colors gives more information.

Radar also has special uses not available with other sensors. Special radars measure winds at the ocean surface. Imaging radars show ocean features not easily seen on photos. They also allow better monitoring of ice on the sea and continental ice sheets, and permit some measurements of snow properties.

After discussion of these topics, we will describe briefly how radar works. Then examples will be shown of various radar images from space, and of some results of wind measurements over the oceans.

Talk Abstract: Radar in Oceanography

Radars in space can add much to our knowledge of the dynamics of the world's oceans. Wind-vector scatterometers provide inputs to global meteorological and wave-forecast models. Imaging radars in space initially were intended to find wave spectra, but now we know that they provide much information on current boundaries, storm effects, shallow-water bottom topography, and other features. Imagers also give us up-to-date information on details of the ice cover on the oceans. Altimeters, the most mature space radars, give information on tides and the geoid.

Radar backscatter strength from the ocean is, surprisingly, governed largely by the small-scale features, capillary waves and short gravity waves. It is this that allows the wind-vector scatterometer to work. We will discuss briefly the mechanisms and their application to scatterometry.

Spaceborne imaging radars usually use synthetic apertures to achieve resolutions of the order of tens of meters, although mesoscale features can also be seen on images from real-aperture radars. Many complications arise in interpreting SAR images of the sea because SAR uses the Doppler effect to produce its fine resolution, and the motions on the sea affect this process. We will discuss SAR principles briefly and point to the complications.

Airborne radars have been used in Russia and Canada for sea-ice monitoring for about 25 years. The Canadian RADARSAT will soon fly with ice monitoring one major application. We have little information on Antarctic sea ice, but images are now available from ESA's ERS-1 SAR, and recent ship-based experiments show some differences between typical ice responses in Arctic and Antarctic.

Dr. Irene Peden

Contact Information:

Dr. Irene Peden
8752 Sand Point Way N. E.
Seattle, WA 98115
USA
Tel: 206-527-9734
Fax: 206-527-1938
E-mail: ipeden@maxwell.ee.washington.edu

Talk Abstract: Laboratory Scale Models for Subsurfact Remote Sensing

Full scale studies of available and developmental field techniques for subsurface electromagnetic probing in the VHF band can be expensive, difficult or hazardous, and analytical models are insufficient in complexity for accurate description of real-world problems. Laboratory scale models provide a complementary alternative approach that is relatively inexpensive and easy to implement, although they have their own limitations. Modeling techniques and instrumentation are discribed that have proven both affordable and useful in studies of down-hole subsurface geophysical remote sensing of two- and three- dimensional dielectric targets. Specific examples illustrate the philosophy and implementation of such models and interpretation of results, together with their significance, as aspects of several studies related to the detection and location of tunnels and buried dielectric objects of finite size.

Talk Abstract: Detection and Localization of Buried Dielectric Targets

Cross-borehole electromagnetic probing with VHF ground-penetrating radar has both commercial and military applications, including location of buried pipes, tunnels and other subsurface objects that call for non-destructive exploration. The cross-borehole configuration maximizes forward scatter to the receiving borehole and offers the best potential for detection, location and geophysical image reconstruction.

Analytical techniques are discussed that relate to electromagnetic scattering from two-dimensional dielectric objects of complex cross section buried in lossy dielectric media. Shallowly buried targets are treated by including an air-earth interface in the formulation for both TM and TE incident fields. Copolarized and cross-polarized fields are examined and it is found that cross-polarized TE field data are relatively insensitive to the presence of the interface, as well as useful for identifying the burial depth. Several techniques are presented for detecting and localizing target position in two dimensions, including cross-correlation of the received signal with a known target signature and modification of the backpropagation operator by filtering of the angular spectrum. Application of some of these techniques to imaging is considered, and some experimental results obtained from a 1/40 scale laboratory model are included for comparison.

Dr. R. Keith Raney

The Johns Hopkins University, Applied Physics Laboratory

Contact Information:

Dr. R. Keith Raney
Senior Scientist
Applied Physics Laboratory
The Johns Hopkins University
Laurel, MD 20723
USA
Tel: 301-953-5384
Fax: 301-953-1093
E-mail: keith.raney@jhuapl.edu

Talk Abstract: The Magellan Radar Imaging Mission to Venus

Designed to fit within apparently impossible restraints, the highly successful Magellan mission of NASA to the planet Venus provided a more complete picture of that planet (98% coverage at 75m pixels) than we have of Earth, and more data than from all previous space missions combined. This presentation outlines the synthetic aperture radar (SAR) that was the heart of the payload, describes the mission, and provides a synopsis of the geophysical results. A video fly-over simulation based on Magellan SAR image and altimetry data will be shown.

(Dr. Raney is a member of the Science Team for Magellan, and served as their radar authority during the design and operational phases of the mission.)

Talk Abstract: A Quasi-Axiomatic Foundation for Synthetic Aperture Rada

Synthetic Aperture Radar (SAR) is a sophisticated and reasonably mature microwave imaging technique, yet SAR system theory and processing strategies usually are treated as disjoint and special topics. This paper presents a unified approach to SAR systems based on six Principles. The first three describe the input space, the output space, and the (non-linear) transformation between the two. The remaining three are Principles of Conservation that apply to estimates of image tone, contrast, and localization, respectively. The Principles are sufficient to explain most first and second order properties of SAR imagery, and provide a useful basis for deeper analysis and explanation of many characteristics characteristic of SAR systems.

(This material was recently given as an invited general lecture at the XXVth URSI General Assembly, Lille, France.)

Dr. John A. Reagan

Professor of Electrical and Computer Engineering, University of Arizona

Contact Information:

Dr. John A. Reagan
University of Arizona
ECE Department
Building 104
Tucson, AZ 85721
USA
Tel: 520-621-6203
Fax: 520-621-8076
E-mail: reagan@ece.arizona.edu

Talk Abstract: Spaceborne Lidar - the LITE Program and Beyond

Abstract available at a later date.

Talk Abstract: New Generation Economical, Eye-Safe Lidars for Aerosol and Water Vapor Sensing

Abstract available at a later date.

Talk Abstract: Spectral Solar RadiometryTechniques and Example Applications for Sensing Aerosols and Water Vapor

Abstract available at a later date.

Prof. Erwin Schanda

Contact Information:

Prof. Dr. Erwin Schanda
St.-Julien-Strasse 2/906
A-5020 Salzburg
AUSTRIA
Tel:
Fax:
E-mail:

Talk Abstract: Millimeter Wave Radiometry of the Atmosphere

Microwave and millimeter wave radiometry and radar became rather well-established methods in remote sensing during the past decade. This happened partly because they can be employed independent of the time of day and almost independent of weather, and partly because of the important spectral features at these wavelengths of environmental media. Therefore, microwaves were first applied to remote sensing of surface features of the earth where rough surface scattering or volume scattering processes carry the information on the natural parameters of soil, sea, ice, snow and vegetation.

The absorption lines of atmospheric constituents in the millimeter and sub-millimeter wave ranges can be utilized to measure with radiometers many trace gases and other parameters, like temperature, throughout the atmosphere. Our long-term investigations comprise local, regional and global observations (including polar regions) of the height distribution of species relevant to the stratosphere ozone chemistry by ground-based, air- and space-borne instruments and to meteorological features (height profiles of liquid and vapour of H20). For the observation of the global distribution of stratospheric O3, H20, ClO and temperature, a multichannel radiometer (MAS) has been flown twice on the ATLAS Shuttle mission in 1992 and 1993.

Some fundamentals of the methods and results of investigations - with emphasis on those carried out by the author's research group - will be presented.

Dr. Thomas A. Seliga

University of Washington

Contact Information:

Dr. Thomas A. Seliga
Electromagnetics and Remote Sensing Laboratory
Department of Electrical Engineering
University of Washington
Seattle, WA 98915-2500
USA
Tel: 206-685-7092
Fax: 206-543-6185
E-mail: seliga@ee.washington.edu

Talk Abstract: Innovative Applications in Radar Meteorology - Focus on Polarimetry

The introduction of polarization-based measurements in radar meteorology in the late 1960's and early 1970's has led to numerous new research and operational applications. These range from improved characterization of hydrometeors to greater accuracy in rainfall rate estimation to new insights into storm structure and dynamics. These advances are leading to improved hydrological prediction of flash flooding, more reliable statistical understanding of the effects of storms on radio propagation links and significant improvements in severe weather warnings. Additional applications are also being recognized; these include remote measurement of aerosol atmospheric washout due to rainfall, monitoring of soil erosion and tracking of weather's effects on ground transportation systems. The development of these events will be presented and placed within the context of the recent introduction of the nation's NEXRAD weather radar system which does not yet have polarimetric capabilities.

Dr. Liang C. Shen

University of Houston

Contact Information:

Dr. Liang C. Shen
Well Logging Laboratory
Department of Electrical Engineering
University of Houston
Houston, TX 77204-4793
USA
Tel: 713-743-4420
Fax: 713-743-4444
E-mail: LShen@UH.EDUbr>

Talk Abstract: Introduction to Electromagnetic Well-Logging and Subsurface Sensing

The technique of sensing the oil and gas reservoir using electro- magnetic waves will be introduced. Various instruments to measure the electrical properties of the earth formation are discussed. Research works involving simulation of these intruments in subsurface environments will be outlined. Efforts in obtaining the conductivity image of the reservoir using array induction tools or cross-borehole systems will be described and some preliminary results will be shown.

Dr. Calvin T. Swift

Microwave Remote Sensing Laboratory, University of Massachusetts at Amherst

Contact Information:

Dr. Calvin T. Swift

Department of Electrical and Computer Engineering
University of Massachusetts at Amherst
College of Engineering
Amherst, MA 01003
USA
Tel: 413-545-2136
Fax: 413-545-4652
E-mail: klemyk@ecs.umass.edu

Talk Abstract: Remote Sensing of Ocean Surface Winds with Microwave Radiometers

As part of a subcontract with the manufacturer of the Defense Meteorological Space Program (DMSP) special sensor microwave/imager (SSM/I), an operational wind speed algorithm was developed by Environmental Research and Technology, Inc. (ERT). The ERT algorithm is based on the "D-Matrix" approach, which seeks a linear relationship between measured SSM/I brightness temperatures and environmental parameters. D-matrix performance was validated by comparing algorithm derived wind speeds with near-simultaneous and colocated measurements made by offshore ocean buoys maintained by the National Oceanic and Atmospheric Administration. The DMSP accuracy requirement of +- 2m/s for wind speed predictions in the range of 3 m/s to 25 m/s was not obtainable with the original version of the D-matrix, which had severe bias and scaling problems. Revisions to the algorithm made at the University of Massachusetts caused it to perform within specifications. Other topics include error budget modeling, alternate wind speed algorithms, and D-matrix performance with one of more inoperative SSM/I channels. Additional research is being done from aircraft to measure high wind speeds in hurricanes. The C-band instrument used for this purpose has measured wind speed as high as 70 m/s.

Talk Abstract: Synthetic Aperture Microwave Radiometers

Aperture synthesis represents a new technology being developed for passive microwave remote sensing of the environment. The concept employs an interferometric technique in which the product from pairs of antennas is sampled as a function of pair spacing. Substantial reductions in the antenna aperture needed for a given spatial resolution can be achieved with this technique. As a result, aperture synthesis could lead to practical passive microwave remote sensing instruments in space to measure parameters such as soil moisture and ocean salinity which require observations at long wavelengths and, therefore, large antennas.

ESTAR is an L-band, aircraft prototype built as part of research to develop this technique. ESTAR is a hybrid real-and synthetic aperture radiometer which employs stick antennas to achieve resolution along track and uses aperture synthesis to achieve resolution across track. Experiments to validate the instrument's ability to measure soil moisture have recently been conducted at the USDA watersheds at Walnut Gulch in Arizona and the Little Washita River in Oklahoma. The results of both experiments indicate that a valid image reconstruction and calibration have been obtained for this remote sensing technique. A more advanced instrument operating at 33 GHz is presently under evaluation.

Dr. Leung Tsang

University of Washington

Contact Information:

Dr. Leung Tsang
Electromagnetics and Remote Sensing Laboratory
Department of Electrical Engineering, FT-10
University of Washington
Seattle, WA 98915
USA
Tel: 206-685-7537
Fax: 206-543-3842
E-mail: tsang1@u.washington.edu

Talk Abstract: Electromagnetic Models in Microwave Remote Sensing with Collective Scattering Effects

In this paper we discuss the electromagnetic models of microwave remote sensing from terrestrial media like snow, ice, soils and vegetation. In the past the common methods of treating such microwave interaction problems are through classical techniques like small perturbation method, and Kirchoff approximation for rough surfaces and radiative transfer theory for discrete scatterers . However, in the microwave remote sensing regime, the inhomogenities are in the proximity of each other on the wavelength scale. Thus the collective scattering effects and the mutual coherent wave interaction among scatterers are to be included. This paper discusses the approaches that have been taken and the difference in the results of the microwave signatures when wave interaction analysis are taken With the advent of modern computers and the development of efficient numerical methods, the computation of the exact solutions of Maxwell's equations for large scale electromagnetic scattering problems are possible. Such simulation techniques have been successfully applied to solve scattering from terrestrial media. We will show results of such solutions of maxwell's equations.

Dr. Werner Wiesbeck

Institute for High Frequency and Electronics, University of Karlsruhe

Contact Information:

Dr. Werner Wiesbeck
Institute for High Frequency and Electronics
University of Karlsruhe
Kaiserstrasse 12
Karlsruhe D 75210
GERMANY
Tel: 49-721-608-2522
Fax: 49-721-691-865
E-mail: ihe@ihewap.etec.uni-karlsruhe.de

Talk Abstract: Polarimetric RCS Measurement, A Survey

Abstract will be available at a later date.

Talk Abstract: System Aspects for Agile Space Borne SAR

Abstract will be available at a later date.

Dr. Dusan S. Zrnic

National Severe Storms Laboratory, NOAA

Contact Information:

Dr. Dusan S. Zrnic
NOAA, Environmental Research Laboratories
National Severe Storms Laboratory
1313 Halley Circle
Norman, OK 73069
USA
Tel: 405-366-0403
Fax: 405-366-0472
E-mail: zrnic@nssla.nssl.uoknor.edu

Talk Abstract: Polarimetric Radar Techniques

The NSSL Doppler radar has been upgraded to include polarimetric measurements and remote operations. I discuss briefly specifics concerning real time computations of polarimetric variables and then focus on their meteorological utility. The question "What is the composition of a cloud and how much of each hydrometeor species are there in the cloud?" is of greatest concern to meteorologists and atmospheric scientists who probe remotely precipitation. We use four polarimetric variables in an attempt to unravel this puzzle. The variables are: reflectivity factor for horizontally polarized wave Zh, differential reflectivity ZDR, differential phase PDP, and the correlation coefficient between the vertically and horizontally polarized co-polar echoes
|rhv(0)|.

For qualitative interpretation of data, physical considerations need to be made. Such procedure is well established so that it is possible with a fair degree of certainty to determine if the hydrometeors are liquid, frozen or mixed. Quantitative information is much harder to obtain and it relies on modeling and judicious combination of the polarimetric variables. As an example it is shown how the difference of reflectivity factors can be used to separate frozen from liquid (or very wet) hydrometeors. Upon separation it is possible to infer the median hydrometeor diameter and the type of distribution. Theoretical and experimental evidence points toward several possible uses of the correlation coefficient between horizontally and vertically polarized echoes. |rhv(0)| provides sharp signatures of the bright band bottom and in addition indicates mixture of rain with hail. It is significant that |rhv(0)| obtained with vertically pointing beams also clearly shows the bottom of the bright band; this observation suggest applications for airborne or spaceborne radars. Specific differential phase and backscatter differential phase shift are obtained from the cumulative differential phase. Examples show that the specific differential phase is an excellent quantifier of intense rainfall (or liquid water content), whereas backscatter differential phase can be used to gauge the upper limit of the contributing sizes. In intense Oklahoma storms we have measured differential attenuation of 2 dB and estimate the attenuation to be over 8 dB, in such events the specific differential phase is the only variable that can provide accurate estimates of liquid water content and rain rate.

Talk Abstract: Operational Doppler Weather Radars in the USA

Much has happened in operational radar meteorology since the last General Assembly. The National Weather Service, the Federal Aviation Administration, and the Air Force Weather Service begun deploying a network of Doppler weather radars (WSR-88D) which are replacing the aging noncoherent systems throughout the country. As of this writing there are 20 WSR-88D radars. Simultaneously the FAA is acquiring Terminal Doppler Weather Radars (TDWR) to monitor hazards and better manage routing of aircraft in and out of terminals at nearly 50 major airports. The two systems are described and primary uses of each are discussed.

A brief description of the WSR-88D system, including primary components, antenna scanning strategy and product dissemination plans are also included. The WSR-88D generates three data fields: reflectivity, mean Doppler velocity, and Doppler spectrum width. These basic data are used by computer algorithms to obtain up to 39 products every five to ten minutes. Examples of products are given to illustrate the capabilities and extreme sensitivity of the radar. For example the radar can detect (signal equals noise) a cloud with a reflectivity factor of - 28 dBZ at a distance of 10 km. This allows measurement of winds in clear air and weak clouds during conditions conducive to storm formation. On several occasions frontal and thermal boundaries have been observed and storms have occurred at the intersections of these boundaries. Other interesting observations include mesocyclone and tornado vortexes, outflow boundaries and jets. There have also been observations of non-meteorlogical nature such as fire plumes, migrating birds and insects.

In contrast to the WSR-88D system the TDWR has a much more specialized mission. Its products are fewer and are highly automated. A description of the system is given and examples of microburst detections and gust front detections are shown.