multi-funtion phased array radar

MULTI-FUNCTION PHASED ARRAY RADAR

Satyanarayana S

AGENDA

• Evolution of RADAR Technology

• Issues and Challenges

• Phased Array RADARS

• Components of a Phased Array RADAR

• Future Technologies

CONVENTIONAL RADAR

Oct-14 Mistral Confidential 3

• Centralized Transmitter• Produce beam pattern by reflector• Scanning achieved by physically moving the antenna• Surveillance and tracking method

– Surveillance: Fan-based beam– Tracking: Pencil beam

DISPLAY

TARGET

Transmit and Receive beam feed

ROTATING JOINT

TRANSMITTER

DUPLEX

RECEIVER

PROCESSOR

Data to System

DISH

Continuous Rotation

SINGLE FUNCTION RADARS

PASSIVE PHASED ARRAY RADAR


• Beam shaping without mechanical movement– Phase shifters, Attenuators and Switching elements

HIGH-POWER VARIABLE PHASE SHIFTERS AND ATTENUATORS

DISPLAY

TARGET

Planar Array (Example of 9 radiators, but usually 1000+)

Dist

ribut

ion

TRANSMITTER

DUPLEX

RECEIVER

PROCESSOR

Data to System

Operator / System Requirement

D1

D2

D3

D4

D5

D6

D7

D8

D9

Computer Beam ControlControl

ISSUES & CHALLENGES

• ISSUES

– 80% of the effective RF power is lost

– 95% of prime power is lost

– 20% of RF power is used for detection

• CHALLENGES

– Intense jamming

– Severe clutter

– Very low RADAR cross section

– Rapid reaction/updates

– Multiple Targets

– Mobility/Transportability


ACTIVE PHASED ARRAY RADAR


• T/R module behind each radiating element• Transmitter power distributed through many Power Amplifiers (HPA) • Small signal loss between HPA and LNA (Low-noise Amplifier)

PASSIVE ANTENNA CONNECTS TO HPA & LNA

HPA

LNA

HPA

LNA

TRM1

TARGET

Planar Array

Phase and Amp Control

Beam Steering Computer

Exciter

TRMn

Down Converter

Transmit / Receive Losses

Signal Processing

ADVANTAGES


• Waveguide can be replaced with low-loss cables

• No tube warm-up time

• Replace tube technologies with solid-state technology

• Improved detection sensitivity by improving noise figure

• MTBF better for solid-state electronics than tubes

• Graceful degradation performance with component failures

• Improved detection sensitivity in the presence of clutter

• Prime power requirements are also greatly reduced

ACTIVE SYSTEMS WITH HIGH DUTY CYCLE / LOW PEAK POWER

EVOLUTION

During 1960 – 1970New technologies developed for Space and Military applications


For Commercial applications

Military & Space applications

During 2010 – 2020New technologies developed for commercial applications such as wireless / base station

T/R MODULES

• Receive Path : High Power Switch, Low Noise Amplifier & Band Pass filters• Common Arm : Digital Phase Shifter, Digital Attenuator• Transmit Path : Driver Amplifier and Power Amplifier• DC Power Conditioning : EMI Filter, Buck converters and LDOs• Digital Controls : Phase Shifters, Attenuators, Switches


Switch

High Power Switch

Power AmplifierSwitch

Low Noise Amplifier

Transmitter Path

Receiver PathControls DC Power Conditioning

Switch

50 V

Common Arm

EFFICIENT AND LOW NOISE

ADVANCEMENTS

• GaN Devices– High efficiency (PAE)

– Higher gain per stage

– Easier Impedance matching

– Wider Bandwidth

– High power SPDT

– Low noise Amplifiers


COMPLETE SOLID-STATE

SUB-ARRAY CONCEPT


DIGITAL AT SUB ARRAY LEVEL

Sub array T/R Modules

Beam steering

(Phase & Amplitude)

On-array Components

Receiver (1 … N)Down Converter

ADC

Digital Beam former

Exciter

Digital Signal processor

Sum Beam Difference Beam

Control Computer

FUTURE ACTIVE ANTENNA


T/R Modules Beam steering (Phase and Amplitude)

On-array Components

Transceiver 1 … M per element

Digital Beam former

Digital Signal processor

Control Computer

DIGITAL AT ELEMENT LEVEL

BENEFITS OF DIGITAL BEAM FORMING


INCREASE IN DYNAMIC RANGE DUE TO DISTRIBUTED ADCs

HPA

LNA

HPA

LNA

HPA

LNA

HPA

LNA

RECE

IVER

RECE

IVER

RECE

IVER

RECE

IVER

ADC

ADC

ADC

ADC

Digital Beam Forming

Sum Beam

X1 X2 Xn….

Beam forming

on Digital data

• System Dynamic Range is n times the ADC Dynamic Range

HPA

LNA

HPA

LNA

HPA

LNA

HPA

LNA

Beam Forming

Sum Beam

X1 X2 Xn….

Beam forming on

Analog (RF)

signals

RECEIVER

ADC

• System Dynamic Range is limited by ADC Dynamic Range

MULTI FUNCTIONS

• Enables MPAR to rapidly and adaptively survey the atmosphere, while serving aviation needs

• Simultaneous tracking on multiple targets coming from many directions

• Enables multiple beams at different frequencies in the band, simultaneously


4 Active antenna Fixed Faces (top

view)

Mission A Mission B Mission C

Face 1 Face 3 Face 2 Face 4

Mission D

∆f1 ∆f2 ∆f3 ∆f4

f1 f2 f3 f4

x MHz

y MHz

COST OPTIMIZATION

• Scalable Array size– Enables same array hardware for multiple aperture configurations

• Tile architecture– Reduce interconnections, simplify assembly and test processes

• Low-peak Power– Allows standard surface mount packages

• Exploit Wireless Industry Technology– Leverages commercial manufacturing and test processes

• Replace existing RADARs that are used for weather and aircraft surveillance with MPAR

– Reduced maintenance and improved availability [Higher power transmitter and mechanism for pointing the antenna]

– Savings in uniform maintenance can be very substantial


PHASED ARRAY RADAR ARCHITECTURE

• Difference in the construction of– Transmitter– Antenna– Receiver Chain


ModulesArray

RADAR Manager

Digital Beam Forming

Array Rx * s

Transmit Signal Generation

Power and Cooling

Signal Processing

Tracking Filters To Weapon Systems

SMALL RADAR TECHNOLOGY

• Placement of short-range RADARS about 30kms apart arranged in a network

• Achieves improved weather surveillance compared to todays long range RADAR technologies

• Can be installed next to existing towers and roof tops

• Long-range RADARS fundamentally incapable of providing comprehensive low-level coverage owing to the curvature of the earth

• Short range RADARS require less than 100 watt of average transmit power


Image Courtsey: AFFORDABLE PHASED ARRAY WEATHER RADARS: STARTING TO BECOME A REALITY, by Prof. David J. McLaughlin, Engineering Research Center for Collaborative Adaptive Sensing of the Atmosphere (CASA), Department of Electrical and Computer Engineering, College of Engineering, University of Massachusetts

ARRAY SPECIFICATION


Frequency X-Band

Array 1m x 1m

Average Beam Width 2o x 2o

Azimuth Scan Range ± 45o to ±60o

Elevation Scan Range 0o – 20o (< 3 km)0o – 56o (22 km coverage)

Dual linear transmit and receive polarization

Performs electronic beam steering in azimuth direction while mechanically steering (tilting) the antenna in the elevation direction

TR ModulesPS

APS

APS

APS

APS

APS

A

Passive Antenna

Power Divider / CombinerReference: AFFORDABLE PHASED ARRAY WEATHER RADARS: STARTING TO BECOME A REALITY, by Prof. David J. McLaughlin, Engineering Research Center for

Collaborative Adaptive Sensing of the Atmosphere (CASA), Department of Electrical and Computer Engineering, College of Engineering, University of Massachusetts

DTRM FROM MISTRAL

• GaN based Dual Transmit Receive Module (DTRM)• RF Frequency Range : 3.1 to 3.5 GHz• Transmit Output Power Level : 100W• Receiver Input Power protection : 100 W, 200usec, 20%Duty• Dimensions (in mm for DTRM) : 220x93x33mm• Weight (DTRM) : < 1000 grams• Operating Temperature : -20C to +55C• Cooling : Surface finish for Liquid cooling

on an external cold plate

Oct-14 19Mistral Confidential

SYSTEMS ENGINEERING


Complex Application Platforms

Liquid-cooled, Air-cooled and Conduction-cooled systems

Integration of Multi-Vendor COTS Solutions, SW, HW and RF Engineering

Qualification and Field Trials

Production, Deployment and Maintenance

1

2

3

45

Electronic Warfare

Airborne Telemetry

SONAR

RADAR

SERVICES OFFERED


Complex Application Platforms

Liquid-cooled, Air-cooled and Conduction-cooled systems

Integration of Multi-Vendor COTS Solutions, SW, HW and RF Engineering

Qualification and Field Trials

Production, Deployment and Maintenance

1

2

3

45

THANK YOU


Mistral Solutions Pvt. Ltd.,No.60, 'Adarsh Regent', 100 Ft. Ring Road, Domlur Ext, Bangalore - 56 0 071 IndiaTel: +91-80-3091 2600

Mistral Solutions Inc.,4633 Old Ironsides Drive, Suite 410, Santa Clara, CA 95054, USAPhone: +1-408-705-2240

E-mail: [email protected]