PAR Study-1 JSH 3/28/2005 MIT Lincoln Laboratory Multifunction Phased Array Radar (MPAR) Jeffrey Herd Mark Weber MIT Lincoln Laboratory 20 March 2007

MIT Lincoln Laboratory PAR Study-2 JSH 3/28/2005 Outline Introduction to MPAR Concept MPAR Pre-Prototype Development Roadmap Summary

MIT Lincoln Laboratory PAR Study-3 JSH 3/28/2005 Aging mechanically scanned radars 8 unique types for 4 different missions Over 500 total with redundant spatial coverage Today Future ASR-9 ASR-11 ARSR-3 TDWR ARSR-4 National Air Surveillance Infrastructure State-of-the-art active phased array radars 1 type for all missions: Multifunction Phased Array Radar (MPAR) Efficient coverage and support infrastructure by eliminating redundancy ASR-8 ARSR-1/2 NEXRAD

MIT Lincoln Laboratory PAR Study-4 JSH 3/28/2005 Current Capabilities Maximum Detection Range Coverage Angular Resolution Waveform Scan Period Aircraft 1 m 2 Weather 0 dBZ RangeAltitudeAz.El. Terminal Area Aircraft Surveillance (ASR-9/11) 60 nmi12 nmi60 nmi20,000' 1.4  5o5o >18 pulses PRI ~0.001 sec 5 sec En Route Aircraft Surveillance (ARSR-4) 205 nmi5 nmi 250 nmi 60,000' 1.4  2.0  >10 pulses PRI ~0.001 sec 12 sec Terminal Area Weather (TDWR) 195 nmi100 nmi60 nmi20,000' 11 0.5  ~50 pulses PRI ~0.001 sec 180 sec En Route Weather (NEXRAD) 210 nmi85 nmi 250 nmi 50,000' 11 11 ~50 pulses PRI ~0.001 sec >240 sec

MIT Lincoln Laboratory PAR Study-5 JSH 3/28/2005 Concept MPAR Parameters Active Array (planar, 4 faces) Diameter: 8 m TR elements/face: 20,000 Dual polarization Beamwidth: 0.7  (broadside) 1.0  45  ) Gain: > 46 dB Transmit/Receive Modules Wavelength: 10 cm (2.7–2.9 GHz) Bandwidth/channel: 1 MHz Frequency channels: 3 Pulse length: 1–100  s Peak power/element: 1–10 W Architecture Overlapped subarray Number of subarrays: 300–400 Maximum concurrent beams: ~160 Active Array (planar, 4 faces) Diameter: 8 m TR elements/face: 20,000 Dual polarization Beamwidth: 0.7  (broadside) 1.0  45  ) Gain: > 46 dB Transmit/Receive Modules Wavelength: 10 cm (2.7–2.9 GHz) Bandwidth/channel: 1 MHz Frequency channels: 3 Pulse length: 1–100  s Peak power/element: 1–10 W Architecture Overlapped subarray Number of subarrays: 300–400 Maximum concurrent beams: ~160 Aircraft Surveillance Non cooperative target tracking and characterization Weather Surveillance

MIT Lincoln Laboratory PAR Study-6 JSH 3/28/2005 CONUS Coverage 35% reduction

MIT Lincoln Laboratory PAR Study-7 JSH 3/28/2005 Preliminary Life Cycle Cost Comparison Replacement of legacy systems with MPAR on as-needed basis saves ~ $2.4B over 20-year period Majority of savings comes from reduced O&M costs Replacement of legacy systems with MPAR on as-needed basis saves ~ $2.4B over 20-year period Majority of savings comes from reduced O&M costs Assumptions: –510 $5-10M ea –167 full-size $15M ea –167 terminal-area $5M ea –Legacy O&M = $0.5M per year –MPAR O&M = $0.3M per year $2.4B

MIT Lincoln Laboratory PAR Study-8 JSH 3/28/2005 Tx Peak Power vs. Pulse Compression 10 W / element Compression ratio = 10 1 W / element Compression ratio = 100 TDWR STC On Sensitivity ~ P p NG 2  ~ P p N 3  Module cost ~ P p  Keep P p small, increase N and lengthen  as needed (with pulse compression for range resolution) But long  requires short “fill” pulse for close-range coverage: crucial for terminal- area surveillance Sensitivity ~ P p NG 2  ~ P p N 3  Module cost ~ P p  Keep P p small, increase N and lengthen  as needed (with pulse compression for range resolution) But long  requires short “fill” pulse for close-range coverage: crucial for terminal- area surveillance MPAR Weather Sensitivity P p : Peak power per element N: Number of elements per face G: Antenna gain  : Pulse length For 46-dB MPAR antenna gain

MIT Lincoln Laboratory PAR Study-9 JSH 3/28/2005 Fill-Pulse and Long-Pulse Sensitivity 230 km for long end of fill-pulse range -15 dBZ Assumes 46-dB antenna gain > 2W per element with 30  s long-pulse and 1  s fill-pulse lengths meets sensitivity requirements ~

MIT Lincoln Laboratory PAR Study-10 JSH 3/28/2005 Current civilian ATC primary radars do not measure target altitude –Cooperative (beacon) response is used Proposed ADS-B ATC surveillance is entirely cooperative –MPAR could be used for 3D detection/tracking of noncooperative targets, and back up & verification for ADS-B Current civilian ATC primary radars do not measure target altitude –Cooperative (beacon) response is used Proposed ADS-B ATC surveillance is entirely cooperative –MPAR could be used for 3D detection/tracking of noncooperative targets, and back up & verification for ADS-B High PRF and full bandwidth for target characterization Target ID mode has limited range swath and cannot operate concurrently with other modes Would be used in brief “point and ID” bursts based on external cues High PRF and full bandwidth for target characterization Target ID mode has limited range swath and cannot operate concurrently with other modes Would be used in brief “point and ID” bursts based on external cues Relative Range (m) Velocity (m/s) Height Discrimination ATCRBS reply quantization Mode S reply quantization Target ID MPAR with monopulse Noncooperative Target Surveillance: 3D Tracking

MIT Lincoln Laboratory PAR Study-11 JSH 3/28/2005 Outline Introduction to MPAR Concept MPAR Pre-Prototype Development Roadmap Summary

MIT Lincoln Laboratory PAR Study-12 JSH 3/28/2005 Notional MPAR Pre-Prototype System 4.2 m = element = subarray center 4544 elements 284 bricks 16 subarrays 8 X 1 beam cluster = brick Pre-Prototype radar demonstrates two simultaneous modes –Aircraft and weather surveillance –Beamwidth: ~ 2º az by 2º el (broadside) –Two independent beam clusters Electronic steering ±45º az, ±40º el Up to 8 beams in each 1D cluster –Provides terminal area coverage km (8 W per element, 20  sec pulse ) Subarray 16 Subarray Phase Centers

MIT Lincoln Laboratory PAR Study-13 JSH 3/28/2005 MPAR Pre-Prototype Systems Analysis b Trade off between HPA power, pulse compression ratio, and minimum detectable reflectivity Desired performance achieved with 8W and 20:1 pulse compression

MIT Lincoln Laboratory PAR Study-14 JSH 3/28/2005 Multiple Beam Cluster Array Architecture 1 1 N Digital Beamformer Switched Dual Pol Radiators Dual-Mode T/R Modules M Overlapped Subarray Beamformer Dual Mode Transceivers Freq 1 Freq 2 f1 f2 Channelizer HPA LNA Channelizer Beam Clusters 2 f1 f2 Channelizer HPA LNA Channelizer f1 f2 Channelizer HPA LNA Channelizer Analog Beamformer Digital Receiver Real Time Beamformer Back End Processor Radar Signal Processors analog digital Beamsteering Controller

MIT Lincoln Laboratory PAR Study-15 JSH 3/28/2005 Modular Brick ‘Brick’ Array Architecture Brick approach provides low cost, scalable architecture Open frame concept for easy access –Forced air cooling Chassis modularity –Flexible brick arrangements Standard Eurocard Format T/R Modules T/R Module Card

MIT Lincoln Laboratory PAR Study-16 JSH 3/28/2005 Transient Thermal Analysis Transient thermal analysis –2W, 4W, 8W, 10W peak transmit amplifiers –Varying pulse lengths Includes critical chip level details –Thermal conductivities of device and interfaces 8W peak power with 20 µsec pulse is thermally acceptable Forced Air HPA’s Physical Geometry Time, µsec Temperature, C 85 ° C Thermal ModellingTransient Response T/R Card

MIT Lincoln Laboratory PAR Study-17 JSH 3/28/2005 Dual Mode T/R Module T/R Module design supports two independent beam clusters ‘Pick and place’ surface mount parts reduce packaging / assembly costs Custom RF designs for application-specific components Red = Off the Shelf parts Blue = Custom Parts To Element V-Pol Feed To Element H-Pol Feed

MIT Lincoln Laboratory PAR Study-18 JSH 3/28/2005 8W T/R Module Parts Costs Parts costs driven by HPA chips and PC board fabrication Packaging / test costs not included Current HPA chip costs are nearly linear with RF power Item Quantity Unit Cost Total Cost HPA 2 $23.00 $46.00 Bias 1 $15.00 $15.00 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 Driver 1 $2.50 $2.50 Load 1 $2.00 $2.00 Board 1 $25.00 $25.00 Total = $ v

MIT Lincoln Laboratory PAR Study-19 JSH 3/28/2005 T/R Module Components T/R module utilizes COTS and custom components –Use custom parts only when it reduces cost, or if not available as COTS part COTS Evaluation Boards Vector Modulator Diplexer Combline Filter Custom RF Components LNA Switch (T/R and Pol) HPA Bandpass Filter PC Board

MIT Lincoln Laboratory PAR Study-20 JSH 3/28/2005 T/R Module Status ActionStatusRemarks Select COTS components Order COTS evaluation parts Design custom components Layout custom boards Fabricate custom parts Delivery late March Test COTS evaluation parts Waiting for several parts Test custom partsWaiting for board fab Assemble connectorized module Test fully assembled module

MIT Lincoln Laboratory PAR Study-21 JSH 3/28/2005 Overlapped Subarray Beamformer Overlapped subarray enables multiple beam clusters Tradeoff between analog and digital complexity Prototype X band overlapped subarray successfully demonstrated under MIT LL IR&D –S band version currently in fabrication Overlapped Subarray Architecture Passive Beamformer Layout v

MIT Lincoln Laboratory PAR Study-22 JSH 3/28/2005 Overlapped Subarray Beamformer on RFIC Chip Measured RFIC Beamformer Pattern RFIC beamformer reduces cost, size and weight Programmable weights enable optimized beam patterns and advanced calibration Prototype X band RFIC demonstrated under MIT LL IR&D RFIC CMOS Beamformer Chip 12 Element X band Subarray Ideal Measured

MIT Lincoln Laboratory PAR Study-23 JSH 3/28/2005 Dual Mode Receiver Parts evaluation confirms discreet component performance –SFDR = 70 dB, NF = 5.3 dB, OIP3=34 dBm –Parts costs = $225 EMI modeling and testing of surface mount boards is critical Dual Mode Receiver Architecture Bench Test Dual Mode Receiver v

MIT Lincoln Laboratory PAR Study-24 JSH 3/28/2005 Digital Subarray Beamformer 8 Digital Beam Cluster Processing simulation tool developed for Pre-Prototype MPAR –Identified critical kernels 16 channel FPGA testbed to test and evaluate kernel designs Digital Beamformer Architecture v

MIT Lincoln Laboratory PAR Study-25 JSH 3/28/2005 Preliminary Parts Cost Estimates ComponentPre-PrototypeFull Scale MPAR Antenna Element$1.25 T/R Module$115.00*$40.00** Power, Timing and Control$18.00 Digital Transceiver$12.50$6.25 Analog Beamformer$63.00$15.00 Digital Beamformer$18.00$8.00 Mechanical/Packaging$105.00$25.00 RF Interconnects$123.00***$40.00**** Equivalent Cost per Element - Parts Only $ $ Totals: * Assumes 8W module incl RF board with sequential polarization ** Assumes 2W module incl RF board with sequential polarization *** Assumes standard beamformer in azimuth **** Assumes hybrid tile/brick architecture

MIT Lincoln Laboratory PAR Study-26 JSH 3/28/2005 Outline Introduction to MPAR Concept MPAR Pre-Prototype Development Roadmap Summary

MIT Lincoln Laboratory PAR Study-27 JSH 3/28/2005 Notional MPAR Pre-Prototype Development Schedule Year 1 Year 2 Year 3 Year 4 Concept Development, Design, and Subsystem Prototyping System Fabrication and Assembly Experimental Testing and Evaluation CDR PDRTesting CDR 16 Element Brick Transceiver Waveform Design Systems Analysis 80 Element Subarray Digital Beamformer DBF) Algorithm Dev System Simulation 4544 Element Array 16 Channel DBF System Simulation Test Planning Collect Multimode Data Process Data Report Results Analog and Digital Hardware: Systems Analysis & Signal Processing: Brick Subarray Array Data Collection

MIT Lincoln Laboratory PAR Study-28 JSH 3/28/2005 Summary Key MPAR features –Lower O&M costs –Scalable –Multifrequency –Dual polarization –Digital beamforming (multiple receive beam clusters) –Adaptive control –Low module peak power –Auxiliary mode functions MPAR Pre-Prototype Technology Demonstration Program –Shows path to ultra-low cost implementations –Provides a means to develop and test MPAR concept –Solidifies key technical requirements Critical demos provide early performance and cost data –Dual mode T/R module –Overlapped subarray beamformer –Dual mode receiver –Digital beamformer –Thermal management