Lectures

Dr. Matthias Weiß (Fraunhofer FHR / Germany)

About the lecturer

This lecture provides the basics for the remaining learning modules which will be presented during the Int. Summer School on Radar / SAR. The learning modules are:

• Introduction
  • History of Radar
  • Concepts and Applications of Radar
• Basic of Radar
  • Geometry
  • Radar Equation
  • Matched Filter, & Point Spread Function
  • Resolution
  • Fast and Slow Time
• Scattering
  • Scattering
    
  • Radar Cross Section (RCS)
• Doppler
  • Doppler Effect
  • Doppler Resolution
  • Range-Doppler processing
• Ambiguity Function
  • Characteristics
  • Properties
  • Doppler Tolerance
  • Expansion to radar networks
• Statistical Signal Processing
  • Detection, Estimation

Dr. Paul Rosen (JPL / USA)

About the lecturer

Radar exploits an active, controlled source illuminating distant objects at wavelengths from mm to meters. As such, radar is a unique remote sensing tool that reaches out and touches objects to understand their geometric and dielectric characteristics at a variety of scale sizes. This lecture will provide a broad overview of radar remote sensing science and instrumentation, with emphasis on the uniqueness of radar relative to other sensing techniques, and how the intrinsic backscatter measurements can lead to physical understanding of the earth and planets.

The learning modules of this unit are:

• What is remote sensing?
• Radar Altimeter
• Scatterometry & Sea wind radar
• Polarimetry
  • Polarimetric Representation
  • Polarized Waves
  • Scattering
  • Freeman Decomposition
  • Polarizations Signature & Classification
• Interferometry
• Imaging Radar
  • Properties
• Applications
  • Applications of Interferometric SAR
  • Applications of Polarimetric SAR
• Literature

Prof. Dr. Pierfrancesco Lombardo (University Rome / Italy)

About the lecturer

The modules of the SAR Fundamentals lecture are in:

• SAR Basics
  • SAR configuration
  • Real aperture Radar
  • Frequency approach to SAR
  • Azimuth resolution
  • Range variation of beta
  • Comparison synthetic vs. real aperture
  • maximum synthetic aperture
  • Near field vs. far field antenna array
  • Frequency approach to Squinted SAR
•  SAR imaging modes
  
  • Spotlight
    
  • Hybrid Spotlight - Stripmap mode
    
  • ScanSAR mode
    
  • From SAR to ISAR
• SAR focusing algorithms
  
  • Range Cell migration
    
  • Range-Doppler Algorithm
    
  • Received signal from a point scatterer
    
  • Chirp Scaling Algorithm
    
  • Range Migration Algorithm
• Coherent multi channel SAR/ISAR
  
  • Single platform
    
  • Multiple platform
• Bi- and Multistatic radar missions => MIMO
• Bistatic SAR and virtual Platform
• Distributed ISAR

Dr.-Ing. Stephan Stanko

About the Lecturer

Modern Radar systems are developed for multi-purpose applications. Thus they have to be small, light weight and powersaving.
The solution for these systems is to use modern semiconductor technologies at frequencies of 100 GHz or even
higher combined with modulated continuous wave signals. Especially in the submmwave band very high absolute
bandwidths are feasible which lead to a very high range resolution.
The learning modules of this unit are:
 

• FMCW Radar
  • Signal description
  • Range resolution
  • Linearity
  • FMCW and Doppler
  • Multi targets and FMCW
• mmW-Radar
  • Set-up
  • FMCW signal generation
  • Phase stability
• Applications
  • ground base
    
  • airborne
  • SAR
  • Motion compensation in mmW

Prof. Dr.-Ing. Christoph Gierull (DRDC / Canada)

About the lecturer

The purpose of this lecture is to introduce the participants to aspects of synthetic aperture radar (SAR) in conjunction with
moving target indication (MTI).
Synthetic aperture radar provides high-resolution images of the non-moving ground scene, but fails to indicate and
position moving objects. A short review of the motion-induced effects occurring in SAR images will open this lecture. Like
in special airborne MTI systems, the solution to the SAR MTI problem is to use an array of antennas or subapertures and
several receiving channels to cancel the interfering clutter. Popular methods for the recognition of motion are ATI (Along
Track Interferometry) and DPCA (Displaced phased centre Antenna) applied to a pair of phase centres. ATI yields imagelike
interferograms with high information content but fails for instance for the azimuth re-positioning of moving target
signals interfered by clutter. In contrast, DPCA commonly permits sufficient clutter suppression but also prevents an
accurate repositioning of the moving object in the SAR image. An efficient generalization of DPCA is adaptive space-time
processing (STAP), which can be simplified to frequency-dependent spatial processing in the Doppler domain.
The ATI, DPCA and STAP techniques applied to SAR will be reviewed in this lecture, theoretically analysed and their
performance will be illustrated with data gathered by experimental airborne and space based SAR systems, such as
PAMIR and RADARSAT-2.

Prof. DSc. Alexander Yarovoy

About the lecturer

• Basics antenna parameters and definitions
•  Antennas for RADAR applications
  • parabolic antenna
  • antenna arrays
  • phased array antenna
•  Antenna measurements
•  Power Amplifiers

Prof. Paulo Marques (ISEL / P)

About the lecturer

• Part 1
  • Waveform design
    
  • Waveform classification
    
  • Amplitude, phase and frequency coding
    
  • Direct optimization
    
  • Matched illumination on transmit and on receive
    
  • Applications and practical examples
• Part 2:
  • MIMO radar
    
  • Introduction
    
  • Principles of operation
    
  • Waveform design for MIMO radar
    
  • Applications and practical examples

Dr. Gianfranco Fornaro (IREA / Italy)

About the lecturer

Due to the capability to provide direct physical measurements, interferometry is the technique that has most pushed the applications of SAR to a wide range of scientific areas and has provided returns to our society in terms of security improvements. For instance, the worldwide most used Digital Elevation Model is a result of a Space Shuttle mission wholly dedicated to SAR interferometry.
Repeat pass differential interferometry and its evolution to Persistent Scatterers Interferometry, which allows accurate localization of ground targets and the monitoring of possible displacements to a mm/yr order, has been a breakthrough for the application of SAR in the risk monitoring area.Multipass/multiview SAR data are today available for most of the Earth by means of acquisitions carried out by existing sensors over repeated orbits. Such huge amount of data call for the development of new processing techniques that improves the capabilities of the existing technology in terms of accuracy and objectiveness of the measurements. The extension of the interferometric concept to the multidimensional imaging, i.e., 3D and 4D (space-velocity) imaging, is one example along this line.The tutorial concentrates on 3D imaging, also known as SAR Tomography or 3D SAR focusing, and explains how such advanced SAR imaging is the result of a natural evolution process, started from single-baseline interferometry and evolved to model-based multibaseline interferometry. The capability of 3D SAR Tomography to accurately locate ground targets, to generate 3D images, and hence to provide a profiling of the scattering distribution also along the elevation direction and hence also to separate and locate different scatterers interfering in the same pixel, will be shown on real data. Further discussions about the potentialities of 3D imaging associated to the next generation bistatic and multistatic SAR sensors, which will allow acquiring multi-view data simultaneously and repeatedly, are also addressed.

Prof. Dr. Joachim Ender (Fraunhofer FHR / Germany)

About the lecturer

The purpose of this lecture is to introduce the participants to aspects of cognitive radar and of compressed sensing to Radar and synthetic aperture radar (SAR).
Compressed Sensing (CS) techniques represent a mathematical framework for the detection and allocation of sparse signals with a reduction of the actually required number of sensors. Nowadays modern radar systems use high bandwidth, which is linked to high sample rates to fulfill the Shannon-Nyquist theorem condition, and a large number of single elements for phased-array antennas. Often only a small amount of target parameters are of interest, which raises the question of whether CS is not a good way to reduce data size, complexity, weight, power consumption, and cost of radar systems. This lecture addresses some aspects of a CS-radar by presenting generic system architectures and implementation considerations. Three possible applications will be considered: pulse compression, radar imaging, and air space surveillance with array antennas.