Table Of ContentMARCH 2005 VOLUME53 NUMBER 3 IETMAB (ISSN0018-9480)
PART II OF TWO PARTS
SPECIALISSUEONMULTIFUNCTIONALRFSYSTEMS
GuestEditorial .. ... ... ... ...... ... ... ... .. E.D.Adler,M.C.Calcatera,J.-F.Luy,W.D.Palmer,andD.S.Purdy 1005
PAPERS
TheAdvancedMultifunctionRFConcept . ... ... ... .... ..... .... ... ... .G.C.Tavik,C.L.Hilterbrick,J.B.Evins,
J.J.Alter,J.G.Crnkovich,Jr.,J.W.deGraaf,W.HabichtII,G.P.Hrin,S.A.Lessin,D.C.Wu,andS.M.Hagewood 1009
MultifunctionMillimeter-WaveSystemsforArmoredVehicleApplication... ... ... .... ..... ... ... ... J.H.Wehling 1021
TowardMultistandardMobileTerminals—FullyIntegratedReceiversRequirementsandArchitectures ... ... ... ....
.. ... ... .... ... ... ... ... ... ... ... ... ... ... ... ...M.Brandolini,P.Rossi,D.Manstretta,andF.Svelto 1026
TheSix-PortasaCommunicationsReceiver .. ... ... ... ... .... ... ...... ... ... ... ... ... ... ... .T.Hentschel 1039
ADual-BandRFTransceiverforMultistandardWLANApplications ... ... ... ... ... ... ... ... ... ... ... ....
.. ... ..S.-F.R.Chang,W.-L.Chen,S.-C.Chang,C.-K.Tu,C.-L.Wei,C.-H.Chien,C.-H.Tsai,J.Chen,andA.Chen 1048
SignalPathOptimizationinSoftware-DefinedRadioSystems.... ..P.Rykaczewski,D.Pieñkowski,R.Circa,andB.Steinke 1056
High-BandDigitalPreprocessor(HBDP)fortheAMRFCTest-Bed . ... ... ... .... ..... ... ... ... ... S.Mazumder,
J.-P.Durand,S.L.Meyer,W.D.Weaver,J.V.Traverse,C.A.Rynas,G.E.Allshouse,J.E.Toland,Jr.,andJ.P.Biondi 1065
Comprehensive Digital Correction of Mismatch Errors for a 400-Msamples/s 80-dB SFDR Time-Interleaved
Analog-to-DigitalConverter... ... ... ... ... ..... .... ... .... ... ... M.Seo,M.J.W.Rodwell,andU.Madhow 1072
IntegratedAntenna/PowerCombinerforLINCRadioTransmitters .. ... ... .... ..... ... ... .. S.GaoandP.Gardner 1083
AnIntelligentlyControlledRFPowerAmplifierWithaReconfigurableMEMS-VaractorTuner .. ... ... ... ... ....
.. ... ... .... ... ... ... ... ... ..D.Qiao,R.Molfino,S.M.Lardizabal,B.Pillans,P.M.Asbeck,andG.Jerinic 1089
Linearityof -BandClass-EPowerAmplifiersinEEROperation .. ... ... ... ... ... ... ... ... ... ... ... ....
.. ... ... .... ... ... ... ... ... ... ..N.Wang,X.Peng,V.Yousefzadeh,D.Maksimovic´,S.Pajic´,andZ.Popovic´ 1096
ADifferential4-bit6.5–10-GHzRFMEMSTunableFilter. ... .... .... ..... ... ... ... .K.EntesariandG.M.Rebeiz 1103
AReconfigurableBandpassFilterforRF/MicrowaveMultifunctionalSystems.... ..... . W.M.FathelbabandM.B.Steer 1111
InformationforAuthors.. ... ... ... ... ... ... ... ... ... .... ...... ... ... ... ... ... ... ... ... ... ... .... 1117
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Editor-In-Chief
MICHAELSTEER WOLFGANG MENZEL BUMMAN KIM ZOYA POPOVIC KENJI ITOH STEVEN MARSH
NorthCarolinaStateUniv.Univ. of Ulm PohangUniv.Sci.Technol. Univ.ofColoradoatBoulder MitsubishiElectricCorp. MidasConsulting
Raleigh, NC Germany Korea USA Japan U.K.
27695-7911USA email:[email protected] email:[email protected] email:[email protected]:[email protected]:[email protected]
Phone:+19195155191 ANDREASCANGELLARIS AMIR MORTAZAWI DYLAN F. WILLIAMS
Fax:+19195131979 Univ.ofIllinois,UrbanaChampaignUniv.ofMichiganatAnnArbor NIST
email: USA USA USA
[email protected] email:[email protected] email:[email protected] email:[email protected] VITTORIORIZZOLI
ANTTI RÄISÄNEN YOSHIO NIKAWA PETER RUSSER ALESSANDROCIDRONALI Univ.ofBologna
HelsinkiUniv.ofTechnol. Kokushikan Univ. TechnischeUniv.Muenchen Univ.ofFlorence Italy
Finland Japan Germany Italy email:[email protected]
email:[email protected] email:[email protected]:[email protected] email:[email protected]
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IEEETRANSACTIONSONMICROWAVETHEORYANDTECHNIQUES,VOL.53,NO.3,MARCH2005 1005
Guest Editorial
WHAT IS a multifunctional RF system? In the world time-domain multiple access (TDMA), global system for mo-
today, we see many systems that have multiple func- bile communications (GSM), digital cellular system (DCS),
tions: your combination personal digital assistant (PDA), Universal Mobile Telecommunications System (UMTS), per-
cellular phone, and digital camera, the wireless color printer sonal handyphone system (PHS)], networking (the various
you just bought that also serves as a copier, fax machine, flavorsof 802.11,Bluetooth, WiMax, Zigbee), and otherstan-
and scanner, and your hiking buddy’s handheld radio with dards as they emerge and gain commercial viability. In the
integrated global positioning system (GPS). Are these mul- future, one can imagine a handheld multifunctional personal
tifunctional RF systems? This TRANSACTIONS’ Special Issue wireless device incorporating voice and data communications,
wouldmaketheargumentthattheyarenot.Thedistinguishing a GPS navigational system, and perhaps even a short-range
featureofeachofthesystemsmentionedaboveisthatthesepa- radarforcollisionavoidanceonbusycitysidewalks.
ratefunctionsareperformedbyseparatehardwaresubsystems, IntheU.S.military,theU.S.Armyisintheprocessoftrans-
i.e., although the device is capable of performing multiple forming from a heavy tank-centric force structure to a lighter
functions,thereisnosinglearchitecturecapableofperforming fasternetwork-centricforcestructure,whichplacesanincreased
all of these functions. The goal in a true multifunctional RF burdenontheintegrationofRFsystemsintogroundplatforms.
systemistobeabletoreconfigureasinglesignalpathsothatit This burden will be met by implementing surveillance, active
is capable of performing multiple arbitrary RF functions. For protection, communications, command guidance, and combat
acommercialwirelesssystem,thismightbeoneradiocapable identificationsystemswithinthereducedweightandspacere-
ofvoiceanddatacommunicationsoverseveralcommunication quirements of these platforms while staying within tight bud-
bands or a combined automotive radar and data link. For a getaryconstraints.Thisgoallikelycannotbeachievedwithmul-
military platform, it could be one system capable of handling tipleindependentRFsystems.TheobjectiveoftheU.S.Army
communications, sensing (radar), navigation, and battlefield ResearchLaboratory’sMultifunctionRFProgramistodevelop
identification. the architecture, subsystems, and algorithms to meet the re-
This capability places extreme performance requirements quirements of such an integrated sensor suite for application
on the individual components, architecture, and resource to the U.S. Army’s Future Combat Systems and other ground
management of such a system. The antenna must be capable platforms.
of transmitting and receiving signals efficiently over a wide The U.S. Office of Naval Research (ONR) initiated the
frequency bandwidth. The receiver and transmitter circuitry AMRFCProgramin1996tosupportanincreaseinthenumber
willrelyheavilyondirectsamplinganddirectdigitalsynthesis of shipboard topside RF functions, while at the same time,
(DDS), requiring ADCs and DACs with very high sampling accommodating increased requirements for ship signature
ratesanddynamicrange.Giventhenewspectrumofcapabilities reduction and control. The AMRFC Program is focused on a
in arbitrary waveform synthesis, high-speed analog-to-digital proof-of-principledemonstrationoftheconceptofbroad-band
conversion, and field programmable processing, it is now multifunction apertures that are capable of simultaneous
becomingpossibletocreatesuchasystem. performance of a large number of radar, electronic warfare,
Numerouscommercialcompaniesarepursuingresearchand and communications functions from common software pro-
product development in this area. High-speed semiconductor grammable hardware. The AMRFC Program consists of two
technologiesareexpectedtoplayanimportantrole:Theavail- coupled research thrusts. The first is a proof-of-concept array
abilityofdigitalcircuitswithclockfrequenciesbeyond10GHz test-bed demonstrator. At the time of this writing, the U.S.
willinfluencethearchitectureofmultifunctionalRFsystems. NavalResearch Laboratory (NRL) hasjust completed a series
The U.S. military has initiatives for Army ground vehicles of demonstrations of AMRFC at the Chesapeake Bay Detach-
(theFutureCombatSystems),Navyships(theAdvancedMul- ment, near Chesapeake Beach, MD. This system is described
tifunctionRFConcept(AMRFC)Program),andAirForceun- inthepaper byTaviketal.Wehope thatthis TRANSACTIONS’
mannedaerialvehicles(the“Sensorcraft”concept). readerswillfindthisinterestingandhaveanappreciationforthe
One clear commercial application for multifunctional capacityofthisachievementtorepresentaparadigmshift—not
RF systems is in wireless communications, where the soft- justfortheDepartmentofDefense,butalsoforthecommercial
ware-based radio will enable a single device to operate across sectoraswell.
the various communications standards for analog and digital Inadditiontotheproof-of-principledemonstrationarray,the
cellular telephony [Advanced Mobile Phone System (AMPS), ONR’s AMRFC Program is also developing new component
TotalAccessCommunicationsSystem(TACS),NordicMobile technologies that enable new classes of multifunction RF ar-
Telephone (NMT), code division multiple access (CDMA), chitectures.Thisprogramhashistoricallyfundedworld-record
speed DDSs (4.6 GHz achieved by Northrop Grumman), tun-
able filters, channelizers, ADCs, DACs, and highly linear am-
plifier chains. More recent efforts are going toward the devel-
DigitalObjectIdentifier10.1109/TMTT.2005.843470 opment of multifunction component chains for AMRFC-type
0018-9480/$20.00©2005IEEE
1006 IEEETRANSACTIONSONMICROWAVETHEORYANDTECHNIQUES,VOL.53,NO.3,MARCH2005
systemswithanemphasisonalsoimprovingaffordability.This remaining papers discuss wide-band, switchable, and tunable
developmenteffortwillenhanceperformance,functionality,and componentsforuseinmultifunctionalRFsystems.
affordabilityofmultifunctionbroad-bandcomponentsinfuture WewouldliketoexpressourthankstothisTRANSACTIONS’
generationsofAMRFC-typesystems. Editor-in-Chief,MichaelSteer,forsupportingthisproject,toall
TheAirForceResearchLaboratoryinitiatedtheSensorcraft authorsthatrespondedtothisSpecialIssue’sCallsforPapers,
Programin1998.Sensorcraftisahigh-altitudeunmannedaerial and to all of the reviewers for their service. We hope that you
vehicle concept that performs intelligence, surveillance, and find this TRANSACTIONS’ Special Issue interesting and useful,
reconnaissance(ISR)missions.Sensorcraft’skeydevelopment andthatitpromptsyoutogetinvolvedinthisexcitingandchal-
istheintegrationofamultisensormultifunctionalsensorsuite. lengingfield.
SensorsincludeUHFradarwithbothgroundmoving-targetand
synthetic-aperture-imagingmodes,and -bandradarwithboth
air moving-target and ground moving-target modes, operating ERICD.ADLER,GuestEditor
simultaneously with a wide-band communications suite, and ArmyResearchLaboratory
signals intelligence system. Structurally integrated antennas MillimeterWaveBranch
and multifunction capability are key enablers for this system Adelphia, MD 20783-1197 USA
concept.
MARKC.CALCATERA,GuestEditor
What are the remaining challenges that lie ahead for the
Wright-PattersonAFB
microwave engineer to solve? We could speculate that afford-
AirForceResearchLaboratory
abilitycanbeaddressedbymaximizingthereuseofcomponents
Dayton, OH 45433 USA
and increasing simultaneity. This is likely to be achieved with
newRFarchitecturesandrethinkingoftheoverallproblem.For JOHANN-FRIEDRICHLUY,GuestEditor
example,toachievemultiplesimultaneousbeamsontransmit, DaimlerChryslerResearchCenter
both high linearity and efficiency will be needed in order to InlineInspectionDepartment
maintain a high degree of spectral purity over a multioctave Ulm, D-89081 Germany
bandwidth. These two requirements are largely orthogonal in
W.DEVEREUXPALMER,GuestEditor
ourcurrentlypopularclass-Aamplifiers.Themicrowaveengi-
U.S.ArmyResearchOffice
neeringfieldwillneedtolookfornewcomponenttechnologies
EngineeringSciencesDirectorate
andarchitecturalapproachestosolvethesetypesofproblems.
Durham, NC 27709-2211 USA
ThisTRANSACTIONS’SpecialIssuecoverssomeofthemost
recent work in multifunctional RF systems and their compo- DANIELS.PURDY,GuestEditor
nents.Thefirsttwopapersgiveanoverviewofmultifunctional U.S.OfficeofNavalResearch
systems currently under development. The next four papers ElectronicsDivision
discuss various multifunctional system architectures. The Arlington, VA 22217-5660 USA
EricD.Adler(S’84–M’85–SM’99)receivedtheB.S.degreeinelectricalengineeringfromRut-
gersUniversity,NewBrunswick,NJ,in1985,andtheM.S.degreeinelectricalengineeringfrom
TheJohnsHopkinsUniversity,Baltimore,MD,in1990.
He is currently an Electronics Engineer with the Millimeter Wave Branch, Army Research
Laboratory (ARL), Adelphi, MD. Since joining the ARL (formerly Harry Diamond Laborato-
ries) in 1985, his research has involved the design, simulation, and integration of various mi-
crowave and millimeter-wave Army prototype systems. These systems include multifunctional
radarandcommunicationsarchitectures,electronicsupportmeasures(ESMs),andcommunica-
tionintercept(COMINT)programs.HecurrentlyexecutestheARLMultifunctionRFinitiative,
whichaddressestechnologiesforelectronicscanningantennas(ESAs),directdigitalsynthesizers,
wide-bandtransceivers,andprogrammableprocessors.Hiscurrenttechnicalareasofinterestin-
cludethevariousdevelopingmillimeter-waveESAtechnologiesthatincludeRotmanlensbeam-
formers,ferroelectricdelaylines,andmicroelectromechanicalsystems(MEMS)phaseshifters.
Mr.AdlerisPresidentoftheIEEEMicrowaveTheoryandTechniquesSociety(IEEEMTT-S)Washington/NorthernVirginia
Chapter.
IEEETRANSACTIONSONMICROWAVETHEORYANDTECHNIQUES,VOL.53,NO.3,MARCH2005 1007
Mark C. Calcatera (M’86) was born in Detroit, MI, in1949. He receivedthe B.Sc. degree in
electricalengineeringfromtheUniversityofDetroit,Detroit,MI,in1972,andtheM.Sc.degree
fromOhioStateUniversity,Columbus,in1979.HealsoattendedTheUniversityofMichiganat
Ann Arbor from 1980 to 1981. His field of graduate study was in electromagnetics, as well as
microwavecircuitsandsystems.
In1972,hejoinedtheAirForceResearchLaboratory,Wright-PattersonAFB,Dayton,OH,in
theElectronicsTechnologyDivision,RFComponentsBranch,wherehewasinvolvedwiththe
developmentofdiverseRFtechnologiesincludingintegratedfront-ends,single-chipphased-array
transmit/receive(T/R)modules,magnetostaticsurface-wavedevices,RFpowercombiners,GaAs
andInPdevices,monolithicmicrowaveintegratedcircuits(MMICs),microwavecomputer-aided
engineering(CAE)anddevicemodeling,anddigital/RFmixed-signaltechnologies.Since1983,
hehasmanagedtheRFComponentsBranch,AirForceResearchLaboratory,Wright-Patterson
AFB,wherehiscurrentresearchconcernsthedevelopmentofwide-bandadaptableRFcompo-
nentsrequiredforcompactmultifunctionsensorsoffutureAirForcesystems.Hehasauthored
orcoauthoredseveralpapers.Heholdsninepatentsintheareaofmicrowavedevicesandsystems.
Mr. Calcatera has served for several years on the Technical Program Committee (TPC) of the IEEE Microwave Theory and
Techniques Society International Microwave Symposium (IEEE MTT-S IMS) in the area of RF device nonlinear modeling, as
wellastheTPCoftheRFICSymposium.
Johann-FriedrichLuy(F’00)receivedtheDipl.Ing.degree(forhisinvestigationsonheatcon-
ductioninsemiconductorlasers)andtheDr.-Ing.degree(forhisthesisonthefirstsiliconmolec-
ularbeamepitaxy(MBE)-madeIMPATTdiodes)fromtheTechnicalUniversityofMunich,Mu-
nich,Germanyin1983and1988,respectively.
From1989to1996,hewasengagedinresearchonSi/SiGemillimeter-wavedevicesandcir-
cuits (SIMMWICS). From 1996 to 2004, he was Head of the Microwave Department, Daim-
lerChryslerResearchCenter,Ulm,Germany.Hismainprojectshaveconcernsthedevelopment
and application of short-range communication links, research in the field of software config-
urable telematic platforms (software-defined radio), and the area of radio-location techniques.
Since2004,hehasbeenresponsibleforthedepartment’s“InlineInspection”withafocusonthe
diagnosisandtestingofinformationandcommunicationsystems,surveillancesystems,andcor-
respondingfailureanalysistechniques.HeisaLecturerwiththeTechnicalUniversityofMunich.
Hehasauthoredorcoauthoredover50papersinreferredjournalsandsymposiaproceedings.He
coeditedSilicon-BasedMillimeter-WaveDevices(Berlin,Germany:Springer-Verlag,1994).
Dr.LuyisamemberoftheTechnicalProgramCommittee(TPC)oftheIEEEMicrowaveTheoryandTechniquesSocietyInter-
nationalMicrowaveSymposium(IEEEMTT-SIMS).HeisontheEditorialBoardoftheIEEETRANSACTIONSONMICROWAVE
THEORYANDTECHNIQUES,aswellasotherreferredjournals.HeisanInternationalScientificRadioUnion(URSI)memberand
an appointed member of the IEEE Electron Devices Society (EDS) Compound Semiconductor Devices and Circuits Technical
Committee.HewasaDistinguishedLectureroftheIEEEEDSfrom1996to1997.
W.DevereuxPalmer(S’89–M’91–SM’01)wasborninAugusta,GA,in1957.Hereceivedthe
B.A.degreeinphysicsandM.S.andPh.D.degreesinelectricalengineeringfromDukeUniver-
sity, Durham, NC, in1980, 1988, and 1991, respectively. His fieldof graduate study was elec-
tromagnetictheory,anddesign,construction,andtestingofmicrowavecircuitsandsystemsfor
practicalapplications.
From 1991to2001, he was amember oftechnicalstaffwith the MicroelectronicsCenter of
North Carolina (MCNC) Research and Development Institute (RDI), Research Triangle Park,
NC,wherehewasinvolvedwithanumberoftechnologiesincludingsiliconvacuummicroelec-
tronicsformicrowavepoweramplifiers,polymericMEMSstructures,high- high-temperature
superconducting(HTS)filters,wide-bandgapsemiconductorsforpower-electronicsapplications,
radioandopticalcommunicationssystems,andopticalandelectronicpackaging.Hetaughtintro-
ductoryelectromagneticsatDukeUniversityasanAdjunctAssistantProfessorforfoursemesters
from1994to1998.In2000,hebecametheDirectoroftheMCNC–RDIOpticalandElectronic
Packaging Group, where he managed programs in development of lead-free flip-chip bumping
processes,bumpingandassemblyofhigh-densitytileddetectorarraysforparticleaccelerators,andpackagingforOC-768optical
components.SincehisassignmentwiththeU.S.ArmyResearchOffice,Durham,NC,in2001,hehasmanagedextramuralbasic
researchprogramsinradio-wavepropagationmodeling,microwaveandmillimeter-wavecircuitintegration,compactandmulti-
functionalantennadesign,andlow-powercommunicationssystems.
Dr.PalmerisaProfessionalEngineerintheStateofNorthCarolina.HeisamemberofURSICommissionsCandD,theAmer-
icanVacuumSociety,theMaterialsResearchSociety,andSigmaXi.WithintheIEEE,heparticipatesintheAntennasandProp-
agation,Components,Packaging,andManufacturingTechnology,ElectronDevices,MicrowaveTheoryandTechniques,Power
Electronics,andProfessionalCommunicationssocieties.HeservedontheVacuumDevicesTechnicalCommitteefrom1997to
2003. He served as guest editor for the TRANSACTIONS ON ELECTRON DEVICES’ Special Issue on Vacuum Electronics (January
2001).HeisafoundingmemberandcurrentchairoftheACME(AP/CPMT/MTT/ED)localchapterintheEasternNorthCarolina
Section, Region 3.
1008 IEEETRANSACTIONSONMICROWAVETHEORYANDTECHNIQUES,VOL.53,NO.3,MARCH2005
DanielS.Purdy(S’87–M’88–SM’04)wasborninChicago,IL,in1960.HereceivedtheB.S.,
M.S.,andPh.D.degreesinelectricalengineeringfromtheVirginiaPolytechnicInstituteandState
University,Blacksburg,in1988,1989,and1995,respectively.
HeiscurrentlyaProgramOfficerwiththeElectronicsDivision,U.S.OfficeofNavalResearch
(ONR), Arlington, VA. From 1989 to 1997, he was with the Naval Air Warfare Center, China
Lake, CA, where he was involved with the development of wide-band antennas, radar, devel-
opment of radar cross-sectional measurement, and signal-processing techniques. From 1992 to
1994,hewasselectedtoattendtheVirginiaPolytechnicInstituteandStateUniversityonaGov-
ernmentAcademicFellowshipandperformedresearchwiththeSatelliteCommunicationsGroup
intheareaofwide-bandphasedarrays.From1997to2000,hewaswithLockheed-MartinMis-
silesandSpace,Newtown,PA,wherehedevelopedtechniquesforphased-arraycalibrationand
communicationsoptimization.In2000,hereturnedtogovernmentserviceasaProgramOfficer
withtheONR.HeiscurrentlytheProgramManagerresponsibleforelectronicstechnologyde-
velopmentfortheU.S.Navy’sAdvancedMultifunctionRFConcept(AMRFC)electronicallyscannedarraydemonstrator.Healso
servesasanagentforseveralDefenseAdvancedResearchProjectAgency(DARPA)researchprograms.Heholdsfourpatents.
His current research interests include ultrahigh-speed logic, mixed-signal circuits, multifunction RF components, architectures,
and systems.
Dr. Purdy served as President of the Washington and Northern Virginia Chapter of the Aerospace and Electronics Systems
Societyfrom2002to2004.
IEEETRANSACTIONSONMICROWAVETHEORYANDTECHNIQUES,VOL.53,NO.3,MARCH2005 1009
The Advanced Multifunction RF Concept
Gregory C. Tavik, Member, IEEE, Charles L. Hilterbrick, Member, IEEE, James B. Evins, Member, IEEE,
JamesJ. Alter,Member,IEEE,JosephG. Crnkovich, Jr.,JeanW.de Graaf,Member, IEEE,WilliamHabichtII,
Gregory P. Hrin, Member, IEEE, Steven A. Lessin, Member, IEEE, David C. Wu, Member, IEEE, and
Stephen M. Hagewood
Abstract—The goal of the Advanced Multifunction Radio
Frequency Concept (AMRFC) Program is to demonstrate the
integration of many sorts of shipboard RF functions including
radar, communications, and electronic warfare (EW) utilizing
a common set of broad-band array antennas, signal and data
processing,signalgeneration,anddisplayhardware.TheAMRFC
Program was launched in response to the growing number of
topsideantennasonU.S.Navyships,whichhavealmostdoubled
from the ships launched in the 1980s to those launched in the
1990s.TheAMRFCProgramseekstodevelopanddemonstratea
wide-bandgenericactivearrayantennaarchitecturethathasthe
abilitytotransmitandreceivemultiplesimultaneousindependent
beams for radar, EW, and communication functions. This paper
describes a proof-of-principle test-bed that is being developedto
demonstratetheAMRFC.
IndexTerms—Arrayantenna,communications,electronicwar-
fare(EW),multifunctionantenna,radar.
Fig.1. Topsideantennagrowthhasmorethandoubledfromthe1980svintage
I. INTRODUCTION launchedshipstothoselaunchedinthe1990s.U.S.Navyshipclassdesignations
areindicatedontheleft-handside(CVorCVNisanaircraftcarrier,DDGisa
THEROLEofthemodernU.S.Navycontinuestorequire guidedmissiledestroyer,etc.).
higherlevelsoffunctionality,performance,andinteroper-
abilityfromshipboardsystems.Currently,radar,electronicwar-
fare (EW), and communication systems lack the level of inte-
gration sufficient to maximize the performance of each, while
minimizing difficulties associated with own-ship electromag-
netic interference. Additionally, the growth in these systems
has resulted in a significant increase in the number of topside
antennas. Fig. 1 shows a doubling in topside antennas from
1980s-era shipstothe 1990s.This presentsanumber ofprob-
lemsincludingincreasedantennablockage,electromagneticin-
terference, and increased ship radar cross section, as well as
maintenance issues related to multiple systems, each with its
ownuniquesetofspareparts,repairpersonnel,andoperators.
Averydesirablesolutiontomanyoftheseproblemsistohave
one system that could simultaneously support multiple func-
tions through a sharedsetof assets, thus,the emphasisfor the
Advanced Multifunction Radio Frequency Concept (AMRFC)
[1], [2].
Fig. 2. Goal of the AMRFC is to demonstrate the integration of multiple
TheAMRFCisanOfficeofNavalResearch(ONR)-funded shipboardfunctions,includingradar,EW,andcommunicationsintoashared
programtodemonstratetheintegrationofseveralshipboardRF setofarrayantennas,signalprocessing,anddisplayhardware.
functions(radar,EW,andcommunications)utilizingacommon
ManuscriptreceivedMay3,2004;revisedOctober26,2004.Thisworkwas
setofbroad-bandapertures,signalanddataprocessing,signal
supportedbytheOfficeofNavalResearch.
G. C. Tavik, J. B. Evins, J. J. Alter,J. G. Crnkovich,Jr.,J. W.de Graaf, generation, and display hardware. Fig. 2 depicts the AMRFC
W.HabichtII,G.P.Hrin,S.A.Lessin,D.C.Wu,andS.M.Hagewoodare objective.
with the Naval Research Laboratory, Washington, DC 20375 USA (e-mail:
The potential AMRFC payoffs are realized in terms of the
[email protected];[email protected]).
C.L.HilterbrickwaswithNorthropGrumman,Baltimore,MD21203USA. following:
HeisnowwiththeNavalResearchLaboratory,Washington,DC20375USA
• reducednumberoftopsideantennas,thereby,reducingthe
(e-mail:[email protected]).
DigitalObjectIdentifier10.1109/TMTT.2005.843485 shipradarcrosssectionandinfraredsignature;
0018-9480/$20.00©2005IEEE
1010 IEEETRANSACTIONSONMICROWAVETHEORYANDTECHNIQUES,VOL.53,NO.3,MARCH2005
Fig.3. AMRFCtest-bedfunctionalblockdiagramshowingthemajorsubsystems.Allsubsystemsarecontrolledsynchronouslythroughafiber-baseddigital
real-timecontrolnetwork.
• increasedpotentialforfuturegrowthwithoutaddingnew many different RF functional needs currently implemented on
apertures; U.S. Navy ships and, therefore, increases the overall benefit
• tighter control over electronic interference and compati- of the AMRFC. Finally, the test-bed hardware and software
bilityissuesthroughmoreintelligentandagilefrequency architecture are generic and configurable, and not function
management; specific wherever possible. This enables the same system
• functionality primarily defined by software, resulting in resources (e.g., waveform generators, digital beamformers,
significantly lowered upgrade costs, and the ability to aperture subarrays, etc.) to be utilized for severaldifferent RF
quickly address new requirements or add new function- functions,althoughnotnecessarilysimultaneously.
alityandbetterinteroperabilitywithlegacysystems; Three major contractors (Lockheed–Martin, Northrop
• potential to substantially reduce life-cycle costs by re- Grumman, and Raytheon) provided a receive array, transmit
ducing the number of unique spare parts and lower ship array, and digital receiver hardware, respectively, for the
manning by reducing personnel required to operate and proof-of-principle program. A fourth company (General Dy-
maintainequipment; namics)hasprovidedmiddlewareandsoftwaresupport.These
• abilitytodynamicallyallocateandmanagesystemassets subsystems have been integrated and are currently under test
according to functional time-line needs, in terms of fre- andevaluationbyaU.S.Navyteam,ledbytheNavalResearch
quency,transmitpower,transmitandreceiveapertureas- Laboratory (NRL), with U.S. Navy provided hardware and
sets,bandwidth,andpolarization. software into the test-bed for concept test and evaluation at
To demonstrate the feasibility of this new concept, an theChesapeakeBayDetachmentTestFacility,NRL.TheU.S.
AMRFC test-bed has been developed and is currently under- NavyteamalsoincludeskeypersonnelfromtheNavalSurface
going system integration and test. The design of the AMRFC WarfareCenterDahlgrenDivision(NSWCDD),andtheNaval
test-bed (see Fig. 3) has several key features to enable the Air Warfare Center Aircraft Division (NAWCAD) Patuxent
program goals listed above. An early key decision in the River.
AMRFC test-bed architecture was to employ separate receive During the latter part of FY04, the AMRFC team demon-
andtransmitantennaarrays.Thisdecisiondidtwothings.First, stratedtheuseofthedevelopedbroad-bandarraytechnologies
the separation of transmit and receive antennas provides the to simultaneously support radar, EW, and communications re-
transmit-to-receive isolation needed for simultaneous multi- ceive and transmit functionality in the 6–18-GHz band. Test
functionoperation.Second,itallowedthereceiveandtransmit scenarioswereselectedthatdemonstratetheabilitytosupport
arraystobesizedseparatelyforreceiveandtransmitfunction- multiple transmit and receive beams through the arrays, and
ality. In the case of the test-bed, the receive array was sized the ability to reconfigure the test-bed assets to support the di-
to receive up to 36 simultaneous receive beams, versus four verserequirementsofpeacetimeandcombatengagementenvi-
simultaneoustransmitbeams.Theselected6–18-GHzRFband ronments.Somepreliminarytestresultsareprovidedbelow.
addressesthekeybroad-bandcommunicationsandEWopera- OtherworkleadinguptotheAMRFCactivityincludedwide-
tionalissues.Additionally,this wide operatingbandaddresses band RF module and radiator development and system archi-
TAVIKetal.:AMRFC 1011
tecture activities by industry and the other U.S. military ser- towerattheTilghmanIslandTestFacility,NRL,approximately
vices.InApril1997,the ONRsponsoredaWidebandRFSci- 17km across the Chesapeake Bay from the AMRFC test-bed.
ence and Technology Workshop, Orlando, FL. At this work- The -bandterminalwasthentransferredtoaboatandlater
shop,membersofindustrypresentedpapersonwide-bandtech- to an aircraft to demonstrate the ability to track and maintain
nologyworkinmultifunctionRFsystems,wide-bandradarsys- thelinkwhilesteeringthebeam.
tems, wide-band EWsystems, wide-band communicationsys- TheSatComlinksdemonstrationconsistedofone -band
tems,andphotonicandelectronictechnologysupportingthefu- commercial satellite link and one -band Defense Satellite
tureapplicationofmultifunctionRFsystems[3]–[6].Addition- CommunicationSystem(DSCS)link.The -bandlinktrans-
ally,therehasbeenasignificantamountworkinmultifunction ferred data between the test-bed and a remote earth station
antennasystemsoverthepastseveralyears.However,mostof through a satellite over the Atlantic Ocean. Due to the small
thisworkhasbeenfocusedontheapertureitself,andsuitedpri- size of the AMRFC proof-of-principle array along with the
marilyforasingleclass(e.g.,communicationsorradar)ofRF power spectral density limits imposed by the International
functionality[7]–[10]. TelecommunicationUnionandFederalCommunicationsCom-
mission, the signal was spread over a wide bandwidth. Note
that this is not meant to be a tactical/fielded waveform, but
II. RFFUNCTIONALITYANDDEMONSTRATION
it does allow demonstration of the array and provide a basis
A. Communications to extrapolate performance to a larger array. The relatively
Fourdifferentcommunicationsbandsliewithintheoperating low data rate (tens of kilobits per second) was demonstrated
frequencybandoftheAMRFCarrays.Twoofthesebands,one by sending text, or other suitable low data-rate information.
in the -band and the other in the -band, are for the mili- The -band DSCS link was demonstrated using a satellite
tary’s Common Data Link (CDL) and Tactical Common Data simulatorlocatedonthetoweratTilghmanIsland.Twomodes
Link (TCDL) systems that carry wide-band data from an air- were demonstrated: a spread-spectrum waveform similar to
crafttoaLOSterminalongroundorship.Theothertwobands that used for the -band SatCom and a phase-shift keying
areforcommunicationsviageostationarysatellites,oneforthe (PSK)waveformsimilartothatusedinactualDSCSterminals.
military -bandsatellitesandoneforthecommercial -band Finally, the transmission of data between the test-bed and a
satellites. remoteearth station through a DSCS satellite located overthe
Thecommunicationssegmentofthetest-bedconsistsofRF AtlanticOceanwasdemonstrated.
distribution, RF downconverters and upconverters, modems,
andotherequipmenttosupportuptosixsimultaneousRFlinks.
B. EW
Thisequipmentiscontrolledbyanembeddedcontroller,which
providestheinterfacetotherestoftheAMRFCtest-bedcontrol One of the primary AMRFC test-bed functions is EW. The
architecture. This enables a common interface to the AMRFC requirements for EW were derived in large part from the U.S.
control network, while allowing various types of terminals to Navy’s long-range effort to improve the survivability of U.S.
be embedded within the test-bed (e.g., legacy modems can be Navy combat ships against both present and future projected
upgraded to programmable modems with minimal impact to threatcapabilities.Themostprominentanddeadlythreatisthe
the rest of the AMRFC system). This modem equipment is antishipcruisemissile(ASCM).
complemented by various displays in the operations shelter EW functions are divided into receive and transmit cate-
(e.g.,datadisplaysandspectrumanalyzeroutput)andauxiliary gories, electronic surveillance (ES) performs passive surveil-
system interface computers to configure and interface to com- lance, and electronic attack (EA) provides active countermea-
munications equipment on the other end of the link from the sures.TheinitialEWdemonstrationeffortwasperformedover
test-bed.ThesixlinksaremadeupoffourCDL-typelinksand the 6–18-GHz operating band of the test-bed and required
two satellite communication (SatCom) links, all of which can broad-band ES receiver assets to provide surveillance and
be receiving data simultaneously and supporting simultaneous timelywarningnecessaryforshipself-protection.
transmissions. TheEShastwofunctions,high-probability-of-intercept/pre-
The CDL links can support 10.7-, 137-, and 274-Mb/s cision-direction-finding (HPOI/PDF) and high gain/high
line-of-sight (LOS) downlinks from an airborne platform, sensitivity (HG/HS). Both ES functions use a state-of-the-art
and the uplink data rates range from a standard 200 kb/s to Wideband Digital Channelized Receiver System technology
10.7 Mb/s, withfuture growth to45 Mb/s. One of the links in adapted to the demands of next-generation ES situational
the AMRFC test-bed is the 274-Mb/s -band downlink. This awareness functions. Multiple embedded antenna elements
-bandlinkusesaremotelylocatedminiaturizedinteroperable from the AMRFC receive array form vertical and horizontal
datalink(MIDL)airborneterminaltotransmitdatatoportable interferometers that provide signals for HPOI environment
groundsupportequipment(PGSE)embeddedintotheAMRFC analysis and precision direction finding in both azimuth and
test-bed.TheremainingCDLtypelinksare -bandsystems, elevation. To scan the environment for low-power radar emis-
which can support 10.7-Mb/s downlink to and a 10.7-Mb/s sions, the HG/HS ES function uses the output from the entire
uplinkfromthetest-bed.Closureofthedownlinkswasdemon- receivearraycombinedinadigitalbeamformerthatdirectsan
stratedbysendingMPEG-2encodedvideodatastreamstothe HGnarrowbeamtosegmentsoftheenvironment.
test-bed and displaying the resultant video in the operations The AMRFC test-bed EA function provides countermea-
shelter. The - and -band air terminals are located in a sures against surveillance and targeting radars and missile
1012 IEEETRANSACTIONSONMICROWAVETHEORYANDTECHNIQUES,VOL.53,NO.3,MARCH2005
seeker radars. These threat radars range from simple nonco-
herentfixedfrequencyradarstocomplexcoherentsystemsthat
employ intra-pulse modulation, multiple simultaneous emis-
sions, and/or frequency agility. The EA techniques employed
against these threats use noncoherent noise-like components
and/or a coherent digital RF memory (DRFM) component
developedaspartoftheAMRFCsignalgenerationsubsystem.
The demonstrations included combat scenarios with multiple
simultaneousEAresponses,againstsurveillance,targeting,and
missileengagements.
Fig. 4. High-band multifunction transmit array supports up to four
C. Radar
simultaneoustransmitbeamconfigurations.Transmitarrayquadrantsmayalso
The AMRFC test-bed radar function is fundamentally a becombinedtoformlargerapertures.
very-low power quasi-frequency-modulated continuous-wave
(FMCW) surface navigation radar. This mode utilizes one fromthesamesignalsource,areusedtodeterminetherawcal-
quadrant of the transmit array, and one channel of the full ibrationdata.Thistest/referencesignalsaretypicallygenerated
receivearray(seeSectionVI).Havingthecapabilitytotransmit by equipment within a function group (see Section III) and,
low peak power, high duty-factor waveforms, and selectively therefore,requiresnospecialsignalgenerators,butratheruses
operateinany or radarbandenablesgreatflexibilityin existing signal-generation equipment. These signals are then
radar operation and interoperability with other RF functions. routedandprocessedinsuchawayastominimizeand,inmany
The low-power navigation radar mode has an instrumented cases,eliminate,allpossiblesourcesoferrorinthecalibration
range to 25 nmi and scans a quadrant ( 50 azimuth at 0 signal distribution chain. Secondly, the calibration function is
elevation) at a 5-s update rate. Through coherently integrating invokedlikeanyotherRFfunctioninthetest-bed.Thismeans
several hundred relatively long high-duty factor pulses, the thatitisafullyintegratedtest-bedfunctionand,therefore,has
radar is capable of detecting objects such as small boats out thesamebasicsoftwarecomponentsasanyotherfunction.This
to several nautical miles. The radar range cell resolution is fullyintegratedapproachpermitscalibrationroutinestobeper-
better than 20 m. Several of the radar modes have a moving formedevenwhileotherfunctionsmaybegoingonand,thus,
targetindicator(MTI)capability,whichisimplementedbyper- wouldlenditselftoat-seaoperationandwouldnotbelimitedto
forming a fast Fourier transform (FFT) on hundreds of pulses in-portmaintenanceoperations.
within the dwell. Through intelligent waveform selection, it The calibration function includes over 20 different modes
is possible to adjust the clutter notch to discern slow-moving thatarecapableofmeasuringtheamplitudeandphaseresponse
targets in strong clutter. Furthermore, since sea clutter returns fortransmitandreceivesubarraysignalpaths,differentphase-
becomede-correlatedafterapproximately10ms,thewaveform shifterandattenuatorsettingsinthetransmitandreceivemod-
dwell interval (over 100 ms) should offer as much as a 20-dB ules,thetransferfunctionsofallexcitersandreceivers,aswell
improvement in clutter cancellation [11]. Finally, it is worth asmanyothermeasurements.Ineffect,thetest-bedcalibration
noting that when the radar is operated at lower power levels, function acts like a built-inspecialized network analyzer. Fur-
there is sufficient electromagnetic isolation between the two thermore,thisdataiscollectedinatimelyfashion.Datacollec-
arraystoeliminateinterferencetoanyotherreceivefunction. tiontimesaregenerallymeasuredinsecondsorminutes.
D. Calibration
III. HARDWAREARCHITECTURE
TheAMRFCtest-bedisajointeffortinvolvingmultiplecon-
A. TransmitArrayDesign
tractorsandseveralU.S.Navylaboratories,eachoneproviding
major subsystems and software components. Such a complex The high-band multifunction transmit array includes 1024
system being developed by many different entities requires a pairs of active radiating elements, segmented into four quad-
highly automated way to diagnose test-bed health and ensure rants of 256 sites each, with each quadrant further subdivided
thatallinterconnectedcomponentsworktogetherasexpectedin into four subapertures. Each subaperture is individually fed
termsofamplitudeandphasealignment.Furthermore,anymis- by one of 16 RF inputs via an array driver interface amplifier.
alignmentsshouldbeabletobetrackedovertimeandpossibly The four quadrants are capable of independent simultaneous
temperature, and be corrected if required. These system level beamforminginanycombinationofquarter,half,orfullarray
calibrations and characterizations are critical to achieving and (Fig. 4).
maintaining accurate beam characteristics, high-fidelity trans- The 1024 array radiators are dual-polarized wide-band el-
mitted and receivedwaveforms withlow distortion,as well as ements capable of providing the required polarization quality
theproperoperationofthetest-bedasawhole. throughoutthescanvolume( 50 azimuth/elevation).Design
The calibration function fulfills the mission outlined above emphasiswasputonwide-bandco-to-cross-polarizationisola-
fortheAMRFCtest-bed[12].Thetest-bedcalibrationfunction tion,voltagestanding-waveratio(VSWR),instantaneousband-
hasatleasttwokeyfeatures.Thefirstfeatureisthemethodby width,scan,andcost.Theradiatorsaremountedonasquaregrid
which test signals are generated and test data is collected. In (rotated by 45 ), with 0.413-in spacing, to provide wide-band
almost all cases, a test signal and a reference signal, derived high-qualitydual-polarizedgratinglobe-freebeamsthroughout
