Date post: | 02-Jul-2015 |
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Multi-mission Phased Array
Radar
By
Madiha Tahseen Shaik
CONTENTS• Introduction
• Overview of MPAR
• The Key to MPAR System
• MPAR Conceptual Design
• Transmitted peak power & Pulse compression
• Dual Polarization
• Air Space Coverage
• Capability Improvements
• Advantages
• Conclusion
INTRODUCTION
What is Phased Array Radar?
Phased Array Radar is an arrangement of
radar elements in array with relative phase
difference between successive elements.
OVERVIEW OF MPAR12m above the ground
There are 3 stories
• Top floor holds Array
antenna
• Middle floor houses for
real time data processing
and data acquisition
equipment
• Bottom floor holds
maintenance tools & test
apparatus
Artistic depiction of the PAR. Due to the effective aperture for different
look directions, the beam width is 1.5◦ at broadside and 2.1◦ at 45◦ off
broadside. Using electronic scanning, the beam can be steered rapidly from
one position to another. Here, this agile beam-steering capability is exploited
for rapid refractivity retrieval.
The Key to MPAR System
MPAR Panel design
Exploded view of the MPAR panel
Mpar conceptual design
MPAR architecture overview
Mpar characteristics
MPAR Parameters
Transmitted peak power
Minimum detectable weather reflectivity versus range for TDWR (black) and for MPAR
using 1 W peak-power TR-modules and a 100 usec pulse length (red), and for MPAR
using 10 W peak-power modules and a 10 usec pulse length (blue).
Pulse compression
MPAR minimum detectible weather reflectivity versus pulse compression ratio at the
short-long pulse transition range (lower curves) and at a range of 230 km(upper curves).
For the assumed 1 usec compressed pulse length, pulse compression ratio is equivalent
to long-pulse length.
Dual polarization
Dual polarized stacked patch antenna configuration and co- and cross-polarized
patterns versus steering angle.
Air space coverage
Airspace coverage comparison between current U.S. operational radar networks
(ASR 9, ASR-11, ARSR-1/2, ARSR-3, ARSR-4, NEXRAD, TDWR) and a conceptual
MPAR network.
Capability improvements
• Weather surveillance
• Non co-operative Aircraft Surveillance
• Air Traffic Control
Weather Surveillance
MPAR’s volumetric scan period for weather surveillance
will be substantially shorter than provided by pencil beam,
mechanically scanned weather radars. The factors supporting
rapid scanning include:
• simultaneous surveillance from each of the four antenna faces
• the ability to very rapidly cover higher elevation angles by
spoiling the transmit beam to cover a large angular volume in a
single radar dwell period
• agile beam capability which enables “beam multiplexing”
and/or adaptive, rapid-update scanning of individual storm
volumes of high operational significance.
Non co-operative Air craft surveillance
MPAR height measurement accuracy
versus range. Twenty-to-one monopulse
angle measurement improvement is
assumed relative to the physical
beamwidth.
Notional Range Doppler image of an
aircraft measured by a radar providing
simultaneous high-range resolution and
a large unambiguous Doppler interval
Air traffic control
• FAA used Automatic Dependence Surveillance-Broadcast(ADS-B) for ATC
• MPAR would not be cost-effective system if considered only as an ADS-B verification system
• But if it is deployed to meet the nation’s weather and co-operative target surveillance needs, MPAR could also provide an effective complement to ADS-B
advantages
• Economical
• No. of radar units are reduced
• Large life span, approximately 30 years
• Large coverage area
Solid state advantages
• Fully Solid state
• Electronic steering depending on phase
shifting
• Failure of one element doesn’t effect the
whole system
conclusion
Concept of multi-mission phased array radar (MPAR) network
described that it could provide high-quality weather and primary
aircraft surveillance capabilities.
It is also being evaluated that a Multi-function Phased Array
Radar (MPAR) is a possible cost-effective replacement for aging
weather and aircraft tracking radars.