Digital Array Radar Technology Development

1. Digital Array Radar Technology Development March 20, 2007 Dr. Barry S. Perlman Associate Director for Technology US Army CERDEC Ft. Monmouth, NJ 07703

2. Introduction Development of Digital Array Radar High-Power GaN MMICs Integrated Low-Cost Modules SiRF Integrated Circuits Antenna Subpanel Development Summary/Conclusions

3. DAR Program Overview Objective: Develop technology for a low-cost, air-cooled active electronically scanned radar Application: Air defense, surveillance, counter mortar, surveillance Contributors: Lockheed-Martin MS2 CREE Semiconductor Purdue University Sierra Monolithics

4. Analog Architecture Analog Architecture Analog Architecture Analog Architecture DAC DAC DAC DAC DAC DAC Proven Approach Proven Approach • • Proven Approach Proven Approach • • Up/ Dn Up/ Up/ Dn Dn Up/ Up/ Dn Dn Up/ Dn Proc Proc High Performance High Performance • • High Performance High Performance • • Convtr Convtr Convtr Convtr Convtr Convtr ADC ADC ADC ADC ADC ADC Large Large DoD DoD Invest Invest • • Large Large DoD DoD Invest Invest • • New Devices in Dev New Devices in Dev • • New Devices in Dev New Devices in Dev • • digital analog Digital Architecture Digital Architecture Digital Architecture Digital Architecture DAC DAC DAC DAC DAC DAC DAC DAC Up/ Up/ Up/ Up/ Dn Dn Dn Dn Up/ Up/ Up/ Dn Dn Dn Up/ Dn DAC DAC DAC DAC DAC DAC DAC DAC Reduces RF Devices Reduces RF Devices • • Reduces RF Devices Reduces RF Devices • • Up/ Up/ Up/ Up/ Dn Dn Dn Dn Up/ Up/ Up/ Up/ Dn Dn Dn Dn DAC DAC DAC DAC DAC DAC DAC DAC Convtr Convtr Convtr Convtr Convtr Convtr Convtr Convtr ADC ADC ADC ADC ADC ADC ADC ADC Increases Op Flexibility Increases Op Flexibility • • Increases Op Flexibility Increases Op Flexibility Up/ Dn Up/ Up/ Up/ Dn Dn Dn • • Up/ Up/ Up/ Up/ Dn Dn Dn Dn Convtr Convtr Convtr Convtr Convtr Convtr Convtr Convtr ADC ADC ADC ADC ADC ADC ADC ADC Proc Proc May Reduce System May Reduce System • • Convtr May Reduce System May Reduce System • • Convtr Convtr Convtr Convtr Convtr Convtr Convtr ADC ADC ADC ADC ADC ADC ADC ADC Cost Cost • • Cost Cost • • Weight Weight • • Weight Weight • • digital to the element Obsolescence Obsolescence • • Obsolescence Obsolescence • • Development of DAR Technology Objective: Low Cost Air Cooled Phased Array Technology Key is Leap to Digital Architecture and Maximal use of Commercial Technology

5. WBG Technology is a Key enabler to achieve an Affordable Radar WBG Front Ends Very High Power High Temperature Operation Very High PAE Minimization of Cooling System Elimination of Circulator & Limiter High Voltage Operation GaN MMICs Panel Technology Low Cost SMT Manufacturing Multi-layer Board technology Air Cooled Low Cost Radiating Element Light Weight Building Block Panel Cross Section

6. Dig GaAs - Based T/R Module Dig GaN Enabling T/R Module Technology • High Efficiency GaN HPA enables lower complexity, cost, and weight air cooled systems. • Higher Power GaN HPAs and robust GaN • LNAs eliminate MMIC chip count & Cost. • Higher voltage operation of GaN enables • a more efficient power system • High Temperature Operation Incorporation of Switch Limiter/LNA on MMIC Possible Low Cost/Power Si Based Technology SOI or SiGe Back End - GaN Front End Phase I Phase II

7. T/R MMIC Block Diagram 2 Stage HPA T/R Switch Gain Block 6 Bit Attenuator 6 Bit Phase Shifter Beamformer Port Antenna Port Gain Block 2 Stage LNA

8. Mask Layout of GaN T/R MMIC

9. Rx & Tx Combined RF RF Power Splitter/Combiner RF Attenuator Tx & Rx Element RF Data & Ctrl Xcvr #1 Xcvr #2 Xcvr #3 Xcvr #4 Test Computer Optical Data Phase Reference DC Power Test Equipment Reference & Power Low Cost Array Undergoing System Testing at LM Four Transceiver Module Test Configuration during Bench Testing - Beamforming test capability for both Tx & Rx modes - Three independent transceiver modules - One Module as common RF & computer interface • Receive sensitivity & linearity goals achieved • Transmitter power & linearity goals achieved • Radar frequency control, transceive mode & BW verified • EMI Immunity verified • Phase locking works across multiple modules • Optical data links operate @ 2.5 GB/sec • Phase calibration works • Distributed beamforming works • Adequate radar phase noise floors achieved Test Configuration Block Diagram Successful Prototype

10. Antenna SubPanel Development Creation of fully integrated receive subpanel array Integration of IC’s into Subarray Panel  Characterization and Package of Full GaN MMIC Mitigation of Active Impedance Versus Scan Angles  Creation of fully integrated Array (T/R) June 2007 April 2007 December 2007 Jan. 2007 Picture of plastic integrated IC. New Array First T/R Array

11. GaN MMIC Front Ends Silicon Digital Beam Former Back End Multiple Receivers on a Single IC Possibly Utilizing Advanced A/D and Multicore Processor Technologies Processor A/D Processor A/D Processor A/D Processor A/D Pushing the logical limits of integration on silicon with multiple receive channels on a single chip. Demonstration of necessary Linearity in Standard Silicon Processes Digital Array Integration RF Out Currently Antenna Array Only – RF out

12. Army advantages: MPAR Offers ……… Lowest cost S-band TRMs Economic production Qty’s Dual-use Cooperation Thru-the-sensor Weather : Own the NIGHT ……… Own the WEATHER….. MPAR advantages: Army Offers ……. GaN investment head start PAR experience @ S-band Large-scale sensor integration Multi-mission radars Business cases Conclusion:Leverage/Share R&D Synergy for the Future ……………………