Update on Low Cost X-band Phased Array Radar Technology for High Resolution Atmospheric Sensing Applications

Transcription

1 WakeNet-Europe Workshop 2013 Day 2: Thursday 16 May 2013 Update on Low Cost X-band Phased Array Radar Technology for High Resolution Atmospheric Sensing Applications David McLaughlin University of Massachusetts Peter Drake Raytheon

2 Today s Aircraft & Weather Surveillance Aircraft at 5k ft Weather at 3 km (~10k ft) Aircraft at 1k ft Weather at 1 km (~3200 ft) widely-spaced radars, low-altitude coverage gaps

3 CASA s Real Problem There is insufficient knowledge about what is actually happening (or is likely to happen) at the Earth s surface where people live. [National Academy of Sciences, 1998] 3.05 km 10,000 ft 1 km 2 km snow wind tornado 4 km 5.4 km gap gap Earth s curvature prevents 72 per cent of the troposphere below 1 km from being observed Horz. Scale: 1 = 50 km Vert. Scale: 1 -=- 2 km RANGE (km) Contributions from government, academia and industry required for solution

4 CASA - Motivation Weather Radar Technology Beyond NEXRAD National Research Council, National Academies Press, 2002 Chair: Prof. Paul Smith Recommendation Far Term: The potential for a network of short-range radar systems to provide enhanced near-surface coverage and supplement (or perhaps replace) a NEXRAD-like network of primary radar installations should be evaluated thoroughly. CASA is funded by the NSF to investigate the potential of such networks; 10 year $50M program, ; CASA2.0 now operational.

5 Problem CASA Concept Weather hazards gap Solution Numerous inexpensive, closelyspaced radars Data Tasking Multiple end users

6 Some theoretical numbers Assumes regular grid 230km(S), 150km(C), 30 km (X) Blanket Coverage 15% Coverage* Large Radar (S/C Bands) Small Radar (X Band) Small Radar (X Band) USA/CONUS 145 8,511 1,277 Europe/OPER A 217 5, France UK Belgium *Critical infrastructure, population centers, borders, etc 6 Large numbers of small radars must be inexpensive, easy to deploy

7 CASA Basic Ideas Close spacing 30 km vs km Short-wavelength X-band vs. S-band Low-power 10 s Watts average power Low cost Hundreds k$ [US] Low infrastructure Multi-user, multi-function Exportable technology Result: improved safety & security via gap free coverage.

8 Sensitivity: Z min & RCS vs. R max Sensitivity of a small radar for weather measurement as a function of range. Such radars achieve worse-case sensitivity of +10 dbz at 30 km Sensitivity of a small radar for detecting aircraft as a function of range (Swerling Type I target with P d = 0.8 and P fa = 10-6 and other parameters given by Pepyne [2008]). R max ~ 30 km for 0 db/10 dbz sensitivity Additional 10 db sensitivity readily

9 From F. Barbaresco, Wake Vortex X-Band Radar Monitoring Paris-CDG airport 2008 Campaign Results & Perspectives, Wakenet3 Europe, db sensitivity to 7 km.

10 X-Band Radar Technology Notional Tower & Building Installations Technology Road Map Array Assemblies Chassis Rear Cover Air-Air Heat Exchanger Phase-phase (2013) Array Frame Assembly Radome Assembly 8 ft 2 Tower Assembly Array Assemblies Tower Assembly Phase-tilt (2011) Array Radar Characteristics: 1 m x 1 m X-band antennas 2 degree pencil beam Single and dual V & H polarization configurations 10 s Watt average power Mechanical Scan (2005)

11 Applications Terminal and Long Range Radar Blind Spot Mitigation Ground Control of UAS in the NAS Wake Vortex Precision Approach Radar Atmospheric Hazard detection Avian Hazard Detection Surveillance Maritime Surveillance Netted Surveillance Radar System Windfarm Resource Area

12 CASA 1 min updates Storm Warning Advantages NEXRAD 5 min updates 2008 National Weather Assoc Meeting Forecast Meteorologist Experiment Test: Predict surface winds 3-6 minutes ahead using CASA+ NEXRAD and NEXRAD only data. Results: 31% redux in estimation error 25% increase in subjective confidence with inclusion of CASA data.

13 OKLAHOMA CITY JOURNAL-RECORD July 1, 2011 New storm radar system praised by Brian Brus The data from a new radar system being tested in Newcastle was so precise that refugees from the storm were able to time the closing of the town's public shelter down to the last minute, City Manager Nick Nazar said."the opportunity to use this advanced technology was very helpful and probably saved lives. It was literally up to the minute and it made a difference. 13

14 Low Altitude Aircraft Detection Airborne XT912 Small radar target detection 10 W,1.2 m 0 20 km Demonstrated Piper & Ultralight detections to 400 AGL, beyond 20 km. See P. Drake et. al., CASA and MSSN, 9 th ICNS Conference, Arlington, VA, May 2010

15 E-Scanned Antenna Technologies First RF Corp Phase steer azimuth Mech tilt elevation 1.5 meter x 1 meter 70 W peak, 30% duty 5 second scan times 2D phase-phase array 1 meter x 1 meter ~ 100 W peak, 30% duty ~ 5 sec volume updates 15

16 Phase-Tilt Antenna Artist Concepts 64 columns (1 m array, 2 0 BW) 16

17 UMass Phase-Tilt Array Components Dogbone apertures MS patch antenna Series-Fed lines MS patch reflector Details in Jorge Salazar s IGARSS Papers: J. L. Salazar, R. Medina, E. Knapp, and D. McLaughlin, Phase-Tilt Antenna Design for Distributed Radar Network for Weather Sensing, Proc. IEEE International Symposium on Geoscience and Remote Sensing, Boston, MA, 2008 (IGARSS 08 J. L. Salazar, E. K. Knapp, D. J. McLaughlin, Dual Polarization Performance of the Phase-Tilt Antenna Array in a CASA Dense Network Radar, Proceedings IEEE Geoscience Remote Sensing Symposium, Hololulu, HI, 2010 (IGARSS 10) 2 W T/R modules 17

18 UMass Laboratory prototype University of Massachusetts prototype demonstrating ~$10k (US) per LRU 18

19 Umass Amherst Phase-tilt Antenna Array Prototype Tests Dual Polarization Performance: Co-pol mis-match <5% to 45 0 (based on LRU NF measurements) -20 db Xpol to 45 0 (calculated) Amplitude(dB) Amplitude(dB) Azimuth Azimuth Pattern Pattern LRU LRU (18x32), (18x32), Taylor-25dB Uniform, SC, n=2, θ SC, θ s :0 deg s :0 deg 00 MP:-1% MP:1.9% V V H -5 H Amplitude(dB) Amplitude(dB) Azimuth Azimuth Pattern Pattern LRU LRU (18x32), (18x32), Taylor-25dB Uniform, SC, n=2, θ SC, θ s :10 deg s :10 deg MP:3.6% MP:3.8% V V H H Amplitude(dB) Azimuth Azimuth Pattern Pattern LRU LRU (18x32), (18x32), Taylor-25dB Uniform, n=2, SC, θsc, θ s :20 deg s :20 deg MP:-1.2% MP:-0.2% V H Co-pol X-pol Azimuth(deg) Azimuth(deg) Azimuth(deg) Amplitude(dB) Azimuth Pattern LRU (18x32), Taylor-25dB n=2, SC, θ s :30 deg Azimuth Pattern LRU (18x32), Uniform, SC, θ s :30 deg MP:3.3% MP:1.6% V V H H Azimuth(deg) Amplitude(dB) Amplitude(dB) Azimuth Pattern LRU (18x32), Taylor-25dB n=2, SC, θ s :40 deg Azimuth Pattern LRU (18x32), Uniform, SC, θ s :40 deg MP:-2.2% MP:0.8% Azimuth(deg) Azimuth(deg) V H V H Amplitude(dB) Azimuth Pattern LRU (18x32), Taylor-25dB n=2, SC, θ s :50 deg Azimuth Pattern LRU (18x32), Uniform, SC, θ s :50 deg MP:-36% MP:-51% Azimuth(deg) J. L. Salazar et al, Dual Polarization Performance of the Phase-Tilt Antenna Array in a CASA Dense Network Radar, Proc. IEEE Geoscience Remote Sensing Symposium, V H 19

20 Manufactured Product FRF

21 Phase-tilt Weather Radar System Tx - 60 MHz Host Computer Gigabit Ethernet IF Transceiver/ Controller Rx - 60 MHz Scan Ctrl (RS422) T/R (RS422) H/V (RS422) Integrated Antenna Assembly 3 components, 2 cables, + software comprise the entire radar system! 21

22 CASA s Phase-tilt Weather Radar Demo Electronic Steering Az ±45 0 Mechanical Steering El -5 to

23 Bush Fire Studies in South Australia

24 Toward a Flat Screen TV Antenna First System Intermediate Next configuration Unit 001 Unit 002A Unit 002B aperture dimensions L x h x D (m) 1.3 x.9 x x.8 x x.8 x.1 aperture weight (kg) <60 Power (includes power supply and motor) EIRP (dbw) AZ beamwidth (deg) EL beamwidth (deg) Elevation Mechanical Pointing range (deg) -15 to to to 90 Azimuth scan range (deg) >+/- 45 >+/- 45 >+/- 45

25 Towards a Flat Screen TV Phased Array Rear face Radiating face (front) Notional dimensions: 1.2 m length 0.8 m height 0.1 m (10 cm!) depth 25

26 Raytheon s LPR Radar: Current Status (2D electronic scanning) Integration and field evaluation of liquid cooled 9.6 GHz Radar #1 commenced early March Radar essentially operating out-of-the-box Air cooled 9.1GHz Radar #2 will be complete Mid May Demos of integrated operation with ASR, as standalone PAR, and as netted system planned over next several months

27 Low Power X-Band Radar Panel CCA Assembly Overview Building Block Panel PWB consists of 128 identical unit cells 18 layer board Slot fed single Patch Radiator Each unit cell contains single SiGe Flip Chip, Linear Regulator, and associated Caps / resistors 4 Power, 4 Logic connectors and 1 RF Connector Radiator Active Components Dual Polar Transceiver MMIC design optimized for low power Weather and Surveillance radar applications

28 LPR Radar- Raytheon s low power WITHIN RADAR HEAD X-band phased array radar X-Band RF CCA Array Agile Pencil Beam Dual Polarization Electronically Scanned IF Data Vaisala 5Ch Digitizer/DSP I/Q Data COTS Platform 5 Channels Configurable to application via waveform parameters Air Surveillance RCL Signal Signal Processor Processor (ASSP) SW largely derived from exportable High Frequency Surface Wave Radar & ATC Application Specific Processing Enhanced Target Tracking Hydrology, Microburst UAS Target Classification BACK END ARRAY FACE RADOME COVER ARRAY PATTERNS COTS based Open Architecture System

29 Infrastructure Friendly Array Assemblies Chassis Rear Cover Air-Air Heat Exchanger Array Frame Assembly Radome Assembly 8 ft 2 Tower Assembly Tower Assembly Top View System readily adaptable to local infrastructure

30 OK to use? Any proprietary concerns? 30