PHOTOGRAMMETRIC ENGINEERING & REMOTE SENSING
January 2017
13
BOOK
REVIEW
Principles of Synthetic Aperture Radar
Imaging: A Systems Simulation Approach
Kun-Shan Chen
CRC Press 2015. 203 pp., diagrams, equations, photos, index.
Hardcover $104, Print ISBN: 978-1-4665-9314-5, $91, eBook ISBN:
978-1-4665-9315-2.
Reviewed by
James J. Reis, GeoSAR Chief Scientist,
Fugro Geospatial, Inc., Frederick, MD, USA.
During the last decade, the development and refinement
of radar remote sensors based on the synthetic aperture
principle has proliferated to the point that these sensors
have almost become a commodity. Modern signal processing
algorithms combined with highly capable digital and analog
components and modular systems have pushed the hardware
and software implementation difficulties into the background.
However the systems engineering required in designing and
implementing a high performance synthetic aperture radar
(SAR) sensor remains both highly mathematical and subtly
nuanced. Furthermore, the imaging data generated by these
sensors frequently contains a variety of artifacts whose
sources often are puzzling and difficult to discern. This book is
well suited for those seeking fundamental insight into many
of these artifacts.
This book is highly mathematical, a necessity to expose
the source of the fundamental issues driving image quality.
Fortunately the mathematical formalism does not get in the
way of understanding critical concepts and deep insights.
Throughout, this book seamlessly integrates a high fidelity
SAR simulation incorporating the nuanced mathematical
principles which permits quantitative evaluation of how
deficiencies in the input data produce undesirable artifacts
in the output imagery. While the book is eclectic in scope,
it emphasizes stripmap airborne systems as the entryway
into SAR sensor technology, since the problems associated
with motion compensation are generally more extreme than
with stationary or space-based systems. However, it does not
address interferometric SAR, and doing so would have diluted
its focus.
The book provides a brief, but useful discussion of the
major signal processing principles employed in the analysis
and design of any SAR system. It builds on this background
by presenting various SAR models of increasing complexity,
emphasizing the constraints and problems entailed by the two
dimensional range-azimuth sampling of the data.
These developments are the foundation for examining the
central issue in SAR processing—motion compensation of
the returns as the platform-sensor combination undergoes
trajectory and velocity deviations. It is precisely at these
points that the mathematical framework is required for deep
understanding. It is to the author’s credit that he skillfully
balances expositing low level details with high level formalism.
This formalism is then adapted for important SAR variants,
including spotlight, space-based, and stationary FMCW
sensors. Uniquely, the book concludes by evaluating several
“autofocus” algorithms via a high fidelity systems simulation
model, which provides an unbiased metric for evaluating
algorithm performance.
Each chapter of book is augmented by important references
to the technical literature. In head-to-head comparisons of
established SAR processing algorithms, the reader is directed
to this literature for lower level algorithmic understanding
and implementation details. While all of the mathematical
variables and constants are identified when first introduced,
it would have been useful to have a summary table to help
refresh the reader’s memory when these symbols reappear
several chapters later.
No book of this scope and depth comes about casually, and
this book is no exception. The book is sharply focused and
seems remarkably free of typos, which is testimony of the care
and attention given by the author and the editors. Principles
of Synthetic Aperture Radar Imaging: A Systems Simulation
Approach has been faithful to its title and as such is an
excellent source for understanding what is required of a first
rate SAR sensor, for users, designers, and developers alike.
Photogrammetric Engineering & Remote Sensing
Vol. 83, No. 1, January 2017, pp. 13.
0099-1112/17/13
© 2017 American Society for Photogrammetry
and Remote Sensing
doi: 10.14358/PERS.83.1.13
