SIGNAL PROCESSING FOR RADAR WITH ARRAY ANTENNAS AND FOR RADAR WITH MICRO ...

190 Pages·2017·57.07 MB·English

SIGNAL PROCESSING FOR RADAR WITH
ARRAY ANTENNAS AND FOR RADAR WITH
MICRO-DOPPLER MEASUREMENTS
Svante Björklund
Blekinge Institute of Technology
Doctoral Dissertation Series No. 2017:02
Department of Mathematics and Natural Sciences
Signal Processing for Radar with
Array Antennas and for Radar with
Micro-Doppler Measurements
Svante Björklund

Blekinge Institute of Technology Doctoral Dissertation Series
No 2015:09
Blekinge Institute of Technology doctoral dissertation series
No 2017:02
Social Sustainability within
the Framework for Strategic
Sustainable Development
Signal Processing for Radar with
Array Antennas and for Radar with
Micro-Doppler Measurements
Merlina Missimer
Svante Björklund
Doctoral Dissertation in
Strategic Sustainable Development
Doctoral Dissertation in
Applied Signal Processing
Department of Mathematics and Natural Sciences
Department of Strategic Sustainable Development
Blekinge Institute of Technology
Blekinge Institute of Technology
SWEDEN
SWEDEN
2017 Svante Björklund
Department of Mathematics and Natural Sciences
Publisher: Blekinge Institute of Technology
SE-371 79 Karlskrona, Sweden
Printed by Exakta Group, Sweden, 2017
ISBN: 978-91-7295-335-2
ISSN:1653-2090
urn:nbn:se:bth-13639
Till min mamma
v

Abstract
Radar(RAdioDetectionAndRanging)usesradiowavestodetectthepresence
ofatargetandmeasureitspositionandotherproperties. Thissensorhasfound
many civilian and military applications due to advantages such as possible
large surveillance areas and operation day and night and in all weather. The
contributionsofthisthesisarewithinappliedsignalprocessingforradarintwo
somewhat separate research areas: 1) radar with array antennas and 2) radar
with micro-Doppler measurements.
Radar with array antennas: An array antenna consists of several small anten-
nas in the same space as a single large antenna. Compared to a traditional
single-antenna radar, an array antenna radar gives higher flexibility, higher
capacity, several radar functions simultaneously and increased reliability, and
makes new types of signal processing possible which give new functions and
higher performance.
The contributions on array antenna radar in this thesis are in three different
problem areas. The first is High Resolution DOA (Direction Of Arrival) Esti-
mation (HRDE) as applied to radar and using real measurement data. HRDE
isusefulinseveralapplications,includingradarapplications,togivenewfunc-
tions and improve the performance. The second problem area is suppression
ofinterference(clutter, directpathjammingandscatteredjamming)whichof-
ten is necessary in order to detect and localize the target. The thesis presents
various results on interference signal properties, antenna geometry and sub-
array design, and on interference suppression methods. The third problem
areaismeasurementtechniquesforwhichthethesissuggeststwomeasurement
designs, one forradar-like measurements andone forscattered signalmeasure-
ments.
Radar with micro-Doppler measurements: There is an increasing interest and
need for safety, security and military surveillance at short distances. Tasks in-
cludedetectingtargets,suchashumans,animals,cars,boats,smallaircraftand
consumerdrones; classifyingthetargettypeandtargetactivity; distinguishing
between target individuals; and also predicting target intention. An approach
is to employ micro-Doppler radar to perform these tasks. Micro-Doppler is
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created by the movement of internal parts of the target, like arms and legs of
humans and animals, wheels of cars and rotors of drones.
Usingmicro-Doppler, thisthesispresentsresultsonfeatureextractionforclas-
sification; on classification of targets types (humans, animals and man-made
objects) and human gaits; and on information in micro-Doppler signatures for
re-identification of the same human individual. It also demonstrates the abil-
itytousedifferentkindsofradarsformicro-Dopplermeasurements. Themain
conclusion about micro-Doppler radar is that it should be possible to use for
safety, security and military surveillance applications.
Preface
The contributions of this thesis are within applied signal processing for radar
in two somewhat separate research areas: 1) radar with array antennas and 2)
radar with micro-Doppler measurements. The thesis consists of two parts:
I An introduction to the areas addressed and publications included in this
thesis:.
1 Motivation and overview.
2 Radar basics.
3 Radar with array antennas.
4 Radar with micro-Doppler measurements.
5 Contributions of the included publications.
II Included publications within the two areas:
A Radar with array antennas.
B Radar with micro-Doppler.
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