Research....
1) Research Project: The
Design and Development of An Imaging Radar
2) Research Project: Real Time Imaging
System for Synthetic Aperture Radar
3) List Of Publication
Research Projcet
The Design and Development of An Imaging Radar
Objective
To design and construct an imaging radar system using
basic RF/microwave component.
Background
Microwave remote sensing is one of the research areas
conducted by the research group in
Radar system
can be grouped into imaging and non-imaging. Under the imaging category of
remote sensing radars are:
1. moving antenna systems (B-scan, PPI)
2. real-aperture side-looking airborne radar (SLAR)
3. Synthetic-aperture side-looking radar (SAR)
The SAR imaging
technique is one of the latest technologies and will be used in this project to
develop the imaging radar for local application.
In this
project, a ground-based imaging radar operating at short-range from a mobile
platform will be constructed. The system proposed here is mobile to permit
examination of a winder variety of objects (such as paddy field and forested
canopy). The radar system will be in C band to provide responses from various
types of vegetation fields.
The imaging
radar developed will be useful for remote sensing of earth terrains in the
country. The data can be integrated into the national Geographical Information
System for policy makers and for monitoring of earth resource.
Some photo of
my research project is availavble in photo section.
Title of Research
Real Time Imaging System for Synthetic Aperture Radar
Objectives
i. To explore various signal processing algorithms.
ii. To present a model for an airborne SAR based on the system geometry.
iii. To develop new technique for a faster and more efficient correlator
design.
iv. To develop a real time SAR system.
Abstract
Synthetic Aperture Radar (SAR) is a two dimension imaging system that processes
the reflected radar signals into an image of the reflecting object. SAR image
processing is typically done using frequency domain, time domain technique or
combination of both. However most of the techniques do not process the data in
real time to produce image. In this research, the study of various SAR imaging
processing techniques will be conducted and technique of reducing the data rate
for real time image processing will be investigated. A model based on the
imaging system geometry and an algorithm for two-dimensional correlation in
order to exploit the natural parallelism to accommodate the higher computation
rate will be presented. The VLSI implementation will be conducted if necessary.
Background
Radar has long been used for military and non-military purposes in a wide
variety of applications such as imaging, guidance, remote sensing and global
positioning. Radar operates by radiating electromagnetic energy through
transmitting antenna and detects the reflected or scattered signal from the
target. However, the image formed by conventional radar (so-called real
aperture radar, RAR) is poor in azimuth resolution. For RAR the smaller the
azimuth beamwidth, the finer the azimuth resolution. In order to obtain high
resolution image one has to resort either to an impractically long antenna or
to employ wavelengths so short that the radar must contend with severe attenuation
in the atmosphere. In airborne application particularly the antenna size and
weight are restricted.
Another way of achieving better resolution from radar is signal processing.
Synthetic Aperture Radar (SAR) is a technique which uses signal processing to
improve the resolution beyond the limitation of physical antenna aperture. In
SAR, forward motion of actual antenna is used to ‘synthesise’ a
very long antenna. SAR allows the possibility of using longer wavelengths and
still achieving good resolution with antenna structures of reasonable size.
SAR has been shown to be very useful over a wide range of applications,
including high resolution geological and topological mapping, sea and ice
monitoring, military surveillance, mining, hydrology, oil pollution monitoring,
oceanography etc. The potential of SAR in a diverse range of application led to
the development of a number of airborne and spaceborne SAR systems. A SAR
system has been developed at Faculty of Engineering,
Synthetic aperture radar (SAR) is an important tool for the collection of
high-resolution all-weather earth images, from both airborne and space-borne
platform. An extensive literature exists on various processing techniques for
generating an image from the radar returns of a SAR. The processing can usually
be broken into two phases: range processing and azimuth processing. Most
coherent radars use some form of modulation or coding of the transmitted waveform
to improve resolution. Resolution enhancement is achieved by two-dimensional
signal processing of the radar data. Range (across-track) resolution is
improved by correlation of the pulse echoes with transmitted pulse so called
range compression. Azimuth (along-track) resolution is improved by
synthetically generating a long antenna aperture, while the real aperture is
relatively small. This operation is known as azimuth compression. Azimuth
compression is based on the fact that each echo reflected from a single point
target has a different phase shift. This phase shift appears to be quadratic in
time and results in a linear frequency shift of the successive pulse echoes.
The azimuth compression operation focuses the echo signal in such a way that a zero
phase shift (zero doppler) remains and integrates the focus echo. As a result
the resolution is improved.
The generation of the picture out of the SAR raw data is a computational
intensive task. The algorithms applied for this generation are based on 2-dimensional
filtering in frequency domain. The transformation between time and frequency
domain is performed by Fast Fourier Transform (FFT) algorithms and requires
most of the processing power of SAR applications. Especially for real time
applications the required processing power cannot be provided by a sequentially
working single processor system. Therefore the parallelization by splitting the
algorithm into independent tasks or distributing autonomous data blocks to
parallel processing units is mandatory. Usually such a processing scheme is
implemented on a multiprocessor system.
Although some architectures for SAR data processing have been developed to
speed-up the processing time, most of the approaches proposed to date are
unable to generate the final image in real time. On the other hand, real time
SAR imaging could play a very important role in applications as diverse as
identifying man made objects on the ground, search and rescue operation or
estimating earth surface activities.
List of Publication
Thesis and Dissertation
·
“PC
Based IC Tester”, Bachelor of Engineering
Thesis,
·
“Transmitter
and Receiver Design of An Airborne Synthetic Aperture Radar”, Master of Engineering Science Thesis,
Journal
·
Y.K. Chan, B.K. Chung and H.T. Chuah, "Transmitter and
Receiver Design of An Experimental Airborne Synthetic Aperture Radar
Sensor," Progress in Electromagnetic Research, PIER 49, page
203-218, 2004.
·
Andy L. Y. Low, Y. K. Chan, S. F. Chien, A. H. You, and T. S.
Guan, “40Gbit/s Polarization Modulation in Ultra-Long Haul Transmission
Systems by Using Optical Phase Conjugators,” IEICE Electronics Express, Vol. 1, No. 13, pg. 386 –
391, 2004.
·
V.C. Koo, , Y.K. Chan, G. Vetharatnam, T.S. Lim, B.K.
Chung, , and H.T. Chuah, “The Masar Project: Design And Development,” Progress
in Electromagnetic Research, PIER 50, page 279-298, 2005.
·
V.C. Koo, , Y.K. Chan and H.T. Chuah, “A New Autofocus Based On
Sub-Aperture Approach”, Journal of Electromagnetic Waves and
Applications, JEWMA, volume 19, number 11, page 1547-1561, 2005.
·
V.C. Koo, Y.K. Chan and H.T. Chuah, “Multiple
Phase Difference Method for Real-Time SAR Autofocus”, Journal of Electromagnetic Waves and
Applications, JEWMA,
volume 20, number 3, page 375-388, 2006
·
V.C. Koo, C.S. Lim and Y.K. Chan, “iSIM - An Integrated Sar Product Simulator
For System Designers And Researchers” Journal of Electromagnetic Waves
and Applications, JEWMA, volume 21, number 3, page 313-328, 2007
·
Chan,
Y., K. and Lim, S., Y., “Synthetic Aperture Radar (SAR) Signal
Generation”, Progress In Electromagnetics Research B (PIER B), PIERB 1,
page 269-290, 2008.
·
Chan,
Y., K. and Koo, V., C., “An Introduction To Synthetic Aperture Radar
(SAR)”, Progress In Electromagnetics Research B (PIER B), PIERB 2, page
27-60, 2008.
Conference Papers
·
Chan
Yee Kit, Azlindawaty, M.K.,
·
T.S.Lim
, Y.K.Chan, V.C.Koo, H.T.Ewe, H.T.Chuah, "Synthetic Aperture Radar Calibration and Field Experiment Setup",
Proceedings of Progress In
Electromagnetics Research Symposium 2005 (PIERS 2005),
·
Y.
K. Chan, V. C. Koo, and T. S. Lim, “Conceptual Design of A High
Resolution, Low Cost X-Band Airborne Synthetic Aperture Radar System”,
Proceedings of Progress In
Electromagnetics Research Symposium 2007 (PIERS 2007), Beijing, China,
pg 1704-1708, March 26-30, 2007.
·
V.
C. Koo, Y. K. Chan, and T. S. Lim, “A Real-time Hybrid Correlator for
Synthetic Aperture Radar Signal Processing”, Proceedings of Progress
In Electromagnetics Research Symposium
2007 (PIERS 2007), Beijing, China, pg 1709-1712, March 26-30, 2007.
·
Mohammad Tariqul Islam, Tan Yee Mun, Chan Yee Kit and Norbahiah Misran, “An Overview of Dual Band
Antenna for WLAN Application”, The 4th International Colloquium on Signal Processing and
its Application (CSPA) 2008, Kuala Lumpur, Malaysia, March 7-9, 2008.
Seminar
·
Azmah A., Noraini I., Safiah Y., Chan, Y.K. & Azlindawaty, M.K “Development of Radar Imaging Sensor for Remote
Sensing Application”, MACRES IRPA Seminar, September 1999
·
Invited
Paper, Chan Y. K.,
·
Invited
Paper, Koo, V.C., Chan, Y.K.,
Research Technical
Report
·
“Conceptual
Design of SAR”, Progress report No. 1 submitted to MACRES as job specification
of “Design and development of SAR”, June 1998
·
“Microwave
System Design and Baseband Processing Hardware Design”, Progress report
No. 2 submitted to MACRES as job specification of “Design and development
of SAR”, September 1998
·
“Microwave
Device Specifications”, Progress report No. 3 submitted to MACRES as job
specification of “Design and development of SAR”, December 1998
Professional
Body
1. Board Of Engineering
2. The Institution of Engineers,
Malaysia (IEM), Graduate member
3. Senior Member, Institute of
Electrical and Electronics Engineers(IEEE),
Professional Activities
·
Organizing
Committee (member), First National Microwave Remote Sensing Seminar,
·
Organizing
Committee (member), Second National Microwave Remote Sensing Seminar,
·
MMU
International Symposium on Information and Communications Technologies (M2usic)
2003 Local Committee member,
·
Organizing
Committee (member), Third National Microwave Remote Sensing Seminar,
·
M2usic2005
Technical Committee,
·
M2usic2006
Technical Committee, 2006.
·
Reviewer
for the MMU International Symposium on Information and Communications
Technologies, since 2004
·
Reviewer
for Journal of Electromagnetic Waves and Applications
(JEMWA), since 2004
·
Reviewer
for Progress Progress in Electromagnetics Research (PIER) since 2004
·
Organizing
Committee (member), Fourth National Microwave Remote Sensing Seminar, 2006.
Professional
Training
Attended
1.
Short
Course on “Synthetic Aperture Radar”, UCLA Extension,
2.
Short
Course on “RF & Analog High Speed Design”, Intel Technology,
3.
Training
on SAR Theory, for CASSAR,
4.
Extended
Training Program 2,
For more detail
please contact me at ykchan@mmu.edu.my
