This two-day course provides a survey of orbital synthetic aperture radar (SAR) systems, past, present, and future. Typical applications are illustrated. Fundamental constraints and trade-offs in system design and performance are introduced. Examples and case studies are used, selected by the Instructor, which, with advance notice, may be augmented by request from prospective students. View course sampler
Instructor:
Dr. Keith Raney has a Ph.D. in Computer, Information and Control Engineering from the University of Michigan, an M.S. in Electrical Engineering from Purdue University, and a B.S. degree from Harvard University. He works for the Space Department of the Johns Hopkins University Applied Physics Laboratory and 2kR,LLC with responsibilities for earth observation systems development, and radar system analysis. He holds six United States and international patents, including the Delay/Doppler Radar Altimeter, the chirp scaling algorithm, and hybrid-polarimetric SAR architecture. He is on NASA's Europa Orbiter Radar Sounder instrument design team. Dr. Raney is on the Science Advisory Group for the European Space Agency's CryoSat, a satellite-based radar altimeter based on his original ideas. Dr. Raney has an extensive background in imaging radar theory, and in interdisciplinary applications using sensing systems. He is the author of over 400 journal and conference articles, and ten book chapters, including “Remote Sensing Space Based Radars”. Chapter 18 in the Radar handbook, 3rd ED. M. Skolnik, editor (2008).
Performance metrics (engineering and applications perspectives)
Performance calculations using simple Excel spread sheet formulations
Design and implementation tradeoffs
Introduction to imaging radar polarimetry
Introduction to SAR interferometry
Overview of current orbital SARs
Systems to be launched in the next five years
Course Outline:
SAR Imagery: Mechanisms and Effects.
— Backscatter. SAR, from backscatter through the radar and processor to imagery. Side- (and down-) looking geometry. Slant-range to ground-range conversion. The microwave spectrum. Frequency and wavelength. Effects of wavelength. Specular (forward and backward), discrete, and diffuse scattering. Shadowing. Cardinal effect. Bragg scattering. Speckle; its cause and mitigation. The Washington Monument.
Applications Overview.
— SAR milestones and pivotal contributions. Typical SAR designs and modes, ranging from pioneering classic, single channel, strip mapping systems to more advanced wide-swath, polarimetric, spotlight, and interferometric designs. A survey of important applications and how they influence the SAR system. Examples will be drawn from SeaSat, Radarsat-1/2, ERS-1/2, Magellan (at Venus), and TerraSAR-X, among others.
System Design Principles.
— Part I, Engineering Perspective: System design of an orbital SAR depends on classical electromagnetic and related physical principles, which will be concisely reviewed. The SAR radar equation. Sampling, which leads to the dominant SAR design constraint (the range-Doppler ambiguity trade-off) impacts fundamental parameters including resolution, swath width, signal-to-(additive) noise ratio, signal-to-speckle (a multiplicative noise) ratio, and ambiguity ratios. Part II, User Perspective: Complex vs real (power or square-root power) imagery. Noise-equivalent sigma-zero. The SAR Greed Factor. The six Axioms that describe top-level SAR properties from the user’s perspective. The SAR Image Quality parameter (the fundamental resolution-multi-look metric of interest to the user) will be described, and its influence will be reviewed on system design and image utility.
SAR Polarimetry.
— Electromagnetic polarimetric basics. A review of the polarimetric combinations available for SAR architecture, including single-polarization, dual polarization, compact polarimetry, and full (or quadrature) polarimetry. Benefits and disadvantages of polarimetric SARs. Hybrid-polarimetric radars. Examples of typical applications. “Free” applications and analysis tools. Future outlook.
SAR Interferometry.
— Basic principles will be introduced assuming a single-pass configuration. These will be extended to the repeat-pass approach, which introduces wavelength and revisit latency (mutual coherency) issues. “Free” applications and analysis tools. Interferometric examples include mapping glacial movement and land subsidence, with state-of-the-art sensitivities as good as 1 mm per year. Future outlook.
Current Orbital SARs. — These include Europe’s ENVISAT, Canada’s Radarsat-2, Germany’s TerraSAR-X and Tandem-X. With requests from students in advance, any (unclassified) orbital SAR may be presented as a case study.
Future Orbital SARs.
— Important examples include ALOS-2 (Japan), RISAT-1 (India), SAOCOM (Argentina), and the Radarsat Constellation Mission (Canada). With advance notice from prospective students, any known forthcoming mission could be presented as a case study.
Open Questions and Discussion.
— Overview of the best professional SAR conferences. Topics raised by participants will be discussed, as interest and curiosity indicate.
Tuition:
Tuition for this two-day course is $1090 per person at one of our scheduled public courses. Onsite pricing is available. Please call us at 410-956-8805 or send an email to ati@aticourses.com.
