Presented to: MPAR Working Group By: William Benner, Weather Processors Team Manager (AJP-1820), FAA Technical Center Date: 20 March 2007 Federal Aviation

Presented to: MPAR Working Group

By: William Benner, Weather Processors Team Manager (AJP-1820), FAA Technical Center

Date: 20 March 2007

Federal AviationAdministration

Multi-function Phased Array Radar (MPAR)

System Cost Evaluation and Cost Risk Reduction

Multi Function Phased Array Radar2Federal Aviation

AdministrationMarch 2007

MPAR Cost Evolution

Concept of Operations (CONOPS)

Concept of Operations (CONOPS)

Operational Requirements (User Needs)

Operational Requirements (User Needs)

Performance Requirements

(Characteristics)

Performance Requirements

(Characteristics)

Drives

Drives

Radar System Architecture &

Design

Radar System Architecture &

DesignDrives

MPAR Cost

Drives

Scale



MPAR Requirements• Assertions

– MPAR Operational Requirements can not be fully developed without a Concept of Operations (CONOPS) for Radar

– Mission Gaps can not be sufficiently identified without operational requirements

– Operational Requirements will drive Architecture/Design which will drive Cost

– The MPAR-WG must avoid the pitfall of a bottom-up approach• Starting with technical requirements for existing radar will lead to

ill-formed requirements for MPAR

• Require a fundamental change in requirements thinking – e.g., 4.8 sec track update – What does the user need? What’s capable?



Example

• Fundamental change in the way radar will scan objects– No longer dependant on rotation rate of radar but

rather on the update rate required to detect/track objects by the operational user

• Will determine radar resource requirement• Will drive architecture cost



Numbers Of Array Faces Transmitting Simultaneously

1 2 4 4 2 4

Numbers of Simultaneous Radar Beams per Array Face

1 1 1 2 4 4

Number Of Radar Signal Processors 1 2 4 8 8 16

Horizon Search Scan Time 2 sec. 2 sec. 2 sec. 1.5 1.5 sec. 1 sec.

Volume Search Scan Time 25 sec. 25 sec. 25 sec. 15 15 sec. 15 sec.

Air Tracks @ .5Hz Track rate 300 300 300 300 300 400

Air Tracks @1Hz Track rate 300 300 300 300 300 400

Clutter tracks 100 100 100 100 100 100

Total % Time for search and track 99% 50% 25% 25% 45% 30%

Weather Scan Standard Update Rate - 180 sec. 120 sec. 60 60 sec. 60 sec.

Weather Scan Fast Update Rate - - 20 sec. 20 20 sec. 20 sec.

Weather Scan Fast Update Search Sector Size

- - 90° Azimuth

18° Elevation

90° Azimuth

18° Elevation

90° Azimuth

18° Elevation

180° Azimuth

18° Elevation

Total % Time for Wx Scan 0% 50% 75% 53% 53% 34 %

Total Radar Time % 99% 100% 100 % 78% 98% 64%

Radar Utilization v. Architecture Study(Worst Case example)



MPAR Cost Influences

Antenna

Signal ProcessorReceiver/Exciter

79%

12%8%

• Technology– Maturity– Economy of Scale– Packaging (commercial vs. military)

• User Needs (Operational Requirements)• Antenna Characteristics (beamwidth, power,

size)• Scan Strategies • Desired Performance



MPAR Cost Influences

• What can we do to affect cost?– Scan Strategy Study

• What are the resource needed to accomplish what must be scanned?

• How often does it need to be scanned?• Can we do it cheaper (simplified beamforming network)?

– Beamwidth Study• Increasing beamwidth decreases the number of T/R Modules

decreasing cost• What is acceptable to the weather community?

– Technology Investigation• Semi-conductor materials• Commercial Parts



T/R Module Cost Study



T/R Module Cost Study

• Focused on:– Transmit/Receive module and its components

• Performance/cost– Emphasis on High Power Amplifier (HPA) and Low

Noise Amplifier (LNA) for T/R Module– T/R Module design for active arrays– Major providers

• Cree, TRIQUINT, MA-COM • Other companies are entering the market (e.g., Nitronix)



T/R Module Model Example

CLC

Tx/Rx CHANNEL

COMBINER

HPA

LNA

LNA

DIVIDER

LIMITERS

CIRCULATOR

TX OUT / RX INto RADIATING

ELEMENT

PRE-DRIVER

DRIVERDIVIDER

COMBINER

TX IN / RX OUT

BEAMFORMER

Typical T/R Module Block Diagram

Example of T/R Module



T/R Module Cost Considerations

• Past paradigms are being changed– Infusion of COTs – Move toward digital designs

• Original objective to estimate cost of T/R module– What is a T/R module ?– How many functions are included in its design?– End objective: Calculate total system cost?

• Trends and tradeoffs can be identified at this point

• Commercial vs. Militarized



High Power RF Amplifier Technologies Investigated• Bipolar Junction Transistors (BJT) - (Si)• Metal Semiconductor Field Effect Transistors (MESFETs) -

GaAs• Pseudomorphic High Electron Mobility Transistor (PHEMT)---

GaAs• Heterojunction Bipolar Transistor (HBT)--- GaAs• MESFET PHEMT– HV GaAs• Metal Semiconductor Field Effect Transistor (MESFET) ---SiC• High Electron Mobility Transistor (HEMT)--- GaN



Major Attributes Being Investigated

• Power Density (w/mm2)• Efficiency (%)• Yield (current)• Wafer size (diameter, mm)• Reliability (H,M,L)• Thermal Conductivity (w/0C)• Maturity (years)



2010GaN HEMT

SiC SITSiC MESFET

SiC HBT

2005HV GaAs

GaAs HEMTSi BJT

103-38A

58%

60%

45% 50%

43%

45%

45%

41%

40%

45% 40%

37%

Radar Thrust – Increased PowerIn

crea

sing

Out

put P

ower

(w

atts

)

UHF L S C XFrequency Band

SiC

Si

GaNSiC

Si BJT

SiC

Si BJT

GaAs

GaN

GaAs

GaN

GaAs

SiC

GaN

Technologies And Frequency Band Support



High Power RF Amplifier TechnologiesS-Band Normalized



Promising Wideband Gap Technologies

• GaN Status (S-Band and above)– May be technology of choice for high frequency high power– Higher gain and efficiency– Emerging technology which is 2-4 years away

• Significant DoD funding (DARPA, ONR, AFRL, ARL) allows development

• Reliability, thermal management need assessment

• SiC Status (S-Band and below)– High-Power performance demonstrated for small quantities– Manufacturability/Reliability needs to be verified– High-Power microwave component maturity 1-3 Years away– Thermal management needs to be assessed

• Other Technologies to Monitor– Gallium Arsenide (GaAs) and its derivatives– Emerging Technologies as they appear (e.g., SiC SIT)



System Cost Initiatives

• Detailed radar cost model – Based on Lincoln Laboratory strawman architecture

• Pre-Prototype• Prototype

• Projected radar cost model– Production for 300 systems

• Scan Strategy Analysis• Conventional radar O&M cost investigation



Recommendations

• Develop high priority products (e.g., CONOPS)– Employ system engineering process– Form working groups

• Continue to explore T/R Module technologies



BACK-UP SLIDES



Radar System Diagram

Phased Array Radar System

Four Face Phased Array

Antenna

RF Receiver, Analog and

Digital Signal Processor

Radar Displays

Radar Control Computer

Radar Facility Structure



Active and Passive Antennas

Cost models not equivalent



MMIC Cost Drivers (e.g., HPA, LNA) • Starting Material costs• Demand• Preparation of material costs• Effective use of wafer “real estate”• Processing yield• Testing• Visual inspection• Packaging

Design tools & tool integration Models Databases Materials Style, e.g., Brick(2D), Tile(3D) Device Placement

• Final test & QA

Die attach approach Feed throughs Wafer/device coatings Assembly Test



MPAR Prototype System Cost

ITEM COSTT/R Module (using RFIC Technology) $Overlapped Sub-Array Beamformer $Digital Beamformer (ASIC) $AC/DC Converters $Radiating Aperture $Structure $Coldplates $RF Combiners $Power/Logic Distribution $Cables $Assembly and Test $Miscellaneous $Total Cost $

Documents

Presented to: MPAR Working Group By: William Benner, Weather Processors Team Manager (AJP-1820), FAA Technical Center Date: 20 March 2007 Federal Aviation