MPAR Trade Studies

1
MPAR Trade Studies

• Mark Weber
• 12 October 2007

2
Lincoln Laboratory ATC Program History
1970 1980 1990 2000
Mode S
Discrete Address Beacon System
Surveillance and Communications
Microwave Landing System
Beacon Collision Avoidance System TCAS
UAS
Moving Target Detector
Communication, Navigation and Surveillance
Airport Surface Detection Equipment
Proc. Augmentation Card
ASR-9
SLEP
Parallel Runway Monitor
GPS Applications
Runway Status Lights
ADS-B
Mode S Surface Comms
Airport Surface Traffic Automation
GCNSS/SWIM
Automation
Terminal ATC Automation
NASA ATM Research
Storm Turbulence
Terminal Doppler Weather Radar
SLEP
ASR-9 Wind Shear Processor
NEXRAD Enhancements
Weather
Multi Function Phased Array Radar
Integrated Terminal Weather System
Aviation Weather Research
Wake Vortex
Corridor Integrated Weather System
3
National Air Surveillance Infrastructure
Future
Today
ADS-B
MPAR
FAA transition to Automatic Dependent
Surveillance Broadcast (ADS-B) dictates that the
nation re-think its overall surveillance
architecture. Needs Weather (national scale and
at airports) ADS-B integrity verification and
backup Airspace situational awareness for
homeland security
4
Todays Operational Radar Capabilities
Weather surveillance drives requirements for
radar power and aperture size Aircraft
surveillance functions can be provided for free
if necessary airspace coverage and update rates
can be achieved Active array radar an obvious
approach, but only if less expensive and/or more
capable than conventional alternatives
5
Outline

• Perspectives on operational needs
• A specific MPAR concept
• Summary

6
Key Questions

• What are the operational drivers for the next
  generation ground weather radar network?
• Improved low altitude coverage, particularly at
  airports?
• Volume scan update rate?
• Capability to observe low-cross section phenomena
  (e.g clear air boundary winds)?
• High integrity measurements, devoid of clutter,
  out-of-trip returns, velocity aliasing, etc.?
• What are requirements for the ADS-B backup
  system?
• Are additional non-cooperative aircraft
  surveillance capabilities needed to maintain
  airspace security?

7
U.S. Airport Weather Radars
Current WSR-88D network does not provide the
near-airport low altitude coverage or update rate
(30 60 sec) needed by terminal ATC
8
Airport Weather Radar Alternatives Analysis
Wind Shear Detection Probability
9
Preliminary Findings

• Easy to make the case for high capability airport
  weather radar at pacing airports (e.g. NYC, ORD,
  ATL, DFW, ....)
• Large delay aversion benefits associated with
  high quality measurements of adverse winds and
  precipitation (gt10M per year per airport)
• Business case for TDWR-like capability at
  smaller airports less convincing
• Alternative solutions may provide adequate safety
  margin
• Weather related delay benefits small
• Implications for MPAR
• Scalability key to realizing cost-effective
  solutions
• Airport-specific integrated observation system
  configurations will be appropriate in some cases
  (e.g. western U.S. dry sites)

10
ADS-B Backup Separation Services Map
11
Required Surveillance Performance (RSP)
Methodology
12
RSP Derived from En Route Radar Capabilities
Only applies for multiple sensors
Supports 5 nmi separation
13
RSP Derived from Terminal Radar Capabilities
Only applies for multiple sensors
Supports 3 nmi separation
14
MPAR RSP Analysis
201 Monopulse
4.4? antenna beamwidth meets Terminal RSP
Separation Error 4.6? antenna beamwidth meets En
Route RSP Separation Error
15
Enhanced Regional Situation AwarenessSystem
Elements
Wide Area
3-D
Visual
SENSORS
Mode-S RCVR
FAA Radars And Data Bases
NORAD TADIL-J
Hi-Res EO Sites
Elevated Sentinel Radars
Redundant Networks
FUSION

• Lincoln facilities provided infrastructure for
  rapid system development
• Radar and camera sites
• FAA data feeds and fusion
• Network connectivity
• Lincoln developed Integrated Air Picture,
  Decision Support, ID, and Visual Warning deployed
  for operational use in NCR

Primary Facility Fusion and Aggregation
Evidence Accrual and Decision Support
Redundant Networks
Fan-out to Multiple Users
USERS
Air Situation Decision Support Display and Camera
Control
Portable Air Situation Display
16
Lincoln Perspectives on Role of FAA Surveillance
Systems

• Current primary/secondary radars as is will
  provide an essential backbone to homeland air
  picture and decision support system
• Enhancement recommendations
• Network compatible interface
• External access to unfiltered target detections
  (amplitude, Doppler velocity, )
• Target height information would be very valuable
• DoD/DHS will deploy ancillary sensor as necessary
  to meet specific operational needs

17
Outline

• Perspectives on operational needs
• A specific MPAR concept
• Summary

18
Concept MPAR Parameters

• Active Array (planar, 4 faces)
• Diameter 8 m
• TR elements/face 20,000
• Dual polarization
• Beamwidth 0.7? (broadside)
• 1.0? (_at_ 45?)
• Gain gt 46 dB
• Transmit/Receive Modules
• Wavelength 10 cm (2.72.9 GHz)
• Bandwidth/channel 1 MHz
• Frequency channels 3
• Pulse length 30 ?s
• Peak power/element 2 W
• Architecture
• Overlapped subarray
• Number of subarrays 300400
• Maximum concurrent beams 160

Aircraft Surveillance
Non cooperative target tracking and
characterization
Weather Surveillance
334 MPARS required to duplicate todays airspace
coverage. Half of these are scaled Terminal
MPARS
19
Concept MPAR Capability Summary

• Airspace coverage equal to todays operational
  radar networks.
• Angular resolution, minimum detectible
  reflectivity and volume scan update rate equal or
  exceed todays operational weather radars
• Ancillary benefits from improved data integrity
  and cross-beam wind measurement
• Can easily support 3-5 nmi separation standards
  required for ADS-B backup
• Can provide non-cooperative aircraft surveillance
  data of significantly higher quality that todays
  surveillance radars
• Altitude information
• Substantially lower minimum RCS threshold

20
2W Dual Mode T/R Module Parts Costs
v
Item Quantity Unit Cost Total
Cost HPA 2 2.37 4.74 SP2T 3
4.00 12.00 LNA 1 1.69
1.69 BPF 1 3.00
3.00 Diplx 1 1.50 1.50 Vect Mod
3 2.14 6.42 Load 1 2.00
2.00 Board 1 20.00 20.00

Total 51.35

• Parts costs driven by SP2T switches and
  multi-layer PC board fabrication
• Packaging / test costs not included

21
Preliminary Parts Cost Estimates
Equivalent Cost per Element - Parts Only
455.75
Totals
164.50
Assumes 8W module incl RF board with sequential
polarization Assumes 2W module and sequential
polarization (updated 18 Sept 2007) Assumes
standard beamformer in azimuth Assumes
hybrid tile/brick architecture with RFIC
overlapped subarray beamformer
22
Summary

• As a community, we are making substantial
  progress in exposing requirements for the Next
  Generation surveillance radar network
• Multifunction, active array (MPAR) approach
  continues to be a leading candidate
• Low cost is the key to success of MPAR
• Commercial approach needed to achieve extremely
  low cost goals
• We are ready to solicit input from industry on
  specific design concepts and cost
• Need to sell concept to policy makers
• Compelling operational application demonstration
• Business case substantiating agency cost savings