"Radio Navigation and Radio Communication - Synergies and Conflicts"

Marconi/SCPNTPanel

PanelModerator:BradParkinson

Panelists:IrwinJacobs,VintCert,JohnCoffi,Mar?nCooper&DavidPayne

Use of Radio Waves - Noteworthy Characteristics Communica?ons

•  DigitalCommunica.ons–resolvingsequenceof“0sor1s”

•  WideRFbandwidthandhighpowertomaximizedatabandwidth,constrainedby“ShannonLimit”inthepresenceofnoise

•  Userscanbepassive(broadcas.ng)orac.ve(full-duplex)

•  TransmiKngusersareusuallyeasilyiden.fied

•  ExplosivegrowthindemandforBandwidth

•  New802.11acspecmayallowprecisionindoorposi.oning

Posi?oning&Timing•  PrecisionTiming(mul.-latera.on)orSignal

Direc2on(orboth)arekeyparameters

•  Keymeasurementisbittransi2on2me(forrangingtypesystems)

•  “SignalSequence”alreadyknown

•  WideBandwidthtoachieve.ming(andhenceranging)precision

•  Useofprocessinggain(anaveragingtechnique)toachieveJammingResistance

•  ForpassiveUsers(e.g.GPSoreLoran),cannotdeterminenumberorloca.ons

•  SatelliteNaviga.onsignalsareextremelyweak

Use of Radio Waves – Selected Techniques/Applications

Communica?ons•  CellPhones(2-way)•  FiberOp.cCable-majordistribu.ontechnique

•  TV–bothsatelliteandterrestrial

•  HF/ShortWave–longrangecommunica.ons

•  NextGenera.on5G

Posi?oningandTiming•  TimeSynchroniza.on

•  Mostapplica.onsrequiremul.ple,.me-synchronizedtransmiaerloca.ons

•  ForGNSS/GPS,signalstrengthisveryweakbutgives24/7Globalcoverage

•  GPSreceiversnowapparentlyover3.5Billion–mostlysmartphones

•  Hi-precisionGPSannualvaluetoUSover$35B

Areas Exampleapplica?ons Avia?on Areanaviga.on,approach,landinguptoCatIII,WAAS,NextGen Agriculture AutoFarming:cropspraying,precisioncul.va.ng,yieldassessment Automo?ve Turn-by-turnguidance,OnStar,driverlesscars Emergency&RescueServices

911,ambulance,fire,police,rescuehelicopters,emergencybeacons,airplaneandshiplocaters,OnStar

IntelligentTransporta?on

Traincontrolandmanagement,UAVs,Intelligenthighways

Military Rescue,precisionweapondelivery,unitandindividualloca.on Recrea?on GeoCaching,controlofmodels,hiking,outdoorac.vi.es Robo?cs&MachineControl

Bulldozers,Earthgraders,miningtrucks,oildrilling

Scien?fic Earthmovementandshape,atmosphere,weatherforecas.ng,climatemodeling,ionosphere,spaceweather,tsunamiwarning,soilmoisture,oceanroughness,windvelocity,snow,ice,andfoliagecoverage,……

SurveyandGIS Mapping,environmentalmonitoring,taggingdiseaseoutbreaks Timing Cellphonetowers,banking,powergrid

Tracking Fleets,assets,equipment,shipments,children,Alzheimer’spa?ents,wildlife,animals,lawenforcements,criminals,parolees,……

PNT Applications – Major Dependency on Comm is in Red

Major Synergies –Nav and Com • CellPhonesandTowers

•  SynchronizeTime•  ProvidequickGPSPosi.on

• AirTrafficControl•  UAVs(Vehicleguidance,TrafficControl,RegulatoryCompliance)• WAAS(IntegrityVerifica.on,Differen.alcorrec.ons)•  NextGen(Automa.cdependentSurveilance)

•  FirstResponders(Police,Fire,Ambulance)•  DispatchandTracking•  UrbanCanyonsChallnge

•  LocalandRegionalDifferen.alCorrec.onLinks

Status of IEEE 802.11 NGP Study Group Next Generation Positioning (NGP)

FromJuly2015Mee.ng:

•  “ExpectedHorizontalAccuracy:XYaccuracyexpectedfortheusecasetosucceed,<1m@90%isarequirementisthatthecomputedloca.onbewithin1mhorizontallyoftheactualloca.on90%ofthe.me”

•  “ExpectedVer.calAccuracy:Zaccuracyexpectedfortheusecasetosucceed,“samefloor@99%”isarequirementisthatthecomputedloca.onbeonthesamefloorastheactualloca.on99%ofthe.me.“0.5m@90%”isarequirementisthatthecomputedloca.onbewithin0.5mver.callyoftheactualloca.on90%ofthe.me”

•  Usecasesnotyetproven…

Another synergy – use of 802.11ac for indoor positioning

Conflicts

•  ScarceSpectrum(FCCAlloca.ons)•  InadvertentInterference(OOB)• CollateralDamage(e.g.tryingtojamCommandalsotakeoutPosi.oning–orreverse)

• PassiveNav(noComm)versustwo-wayNav

0

1

1400 1450 1500 1550 1600 1650

FrequencyinMegaHertz

FrequencyAlloca2onsinGPSFrequencyVicinity

- Proposed:- 40,000TerrestrialBroadband

Transmi\ers

- -5BillionTimesGPSPowerat¼Mile

GPSBand

Problems:Proximity(geographicandRFspectrum)

andPower

Lo-Performance,Narrow-BandGPSReceiversmaybe

madetocopewithHi-PowerAdjacentTransmiaeres

Full-BandGPS

Exis.ngHi-Performance,Full-BandGPSReceiversare

JammedNoKnownSimpleFix(swapoutin10years?)

ScarceSpectrumCom/NavConflict:-Poten.alFCCAuthorizedrepurposingofSpectrum

X

?

Visualizing the Problem - Equivalent Power Ratio

Hi-Power Terrestrial - ¼ mile from GPS

HiPowerTerrestrialNiagara~1BillionWaas

(167feetdropwith64,750cubicfeet/second)

5

Feet

GPS-0.2Waas

(1Tablespoonofwaterpersecondthrough5feet)

SamePowerRa?oof5BilliontoOne

Major Questions

• WhatcancellphonesdotocopewithjammingofPNT?Doesitmaaer?

• CanadjacentbandTerrestrial,wide-bandCommunica.ons(e.g.Ligado)becompa.blewithGPS/GNSS?

• Will5Gor802.11acchangethesynergiesbetweenNavandCom?

• Withthenear-futureadventoffourmajorGNSS,doestheinternetorcellphonesbenefit?

Backups

Adjacent band interference

12

Why the Strong Reaction to changing the adjacent band to high-power applications? • GPSuserssupporttheintroduc?onof

Broadband,butnotattheexpenseofthefounda?onsofGPS-

• HipowerneighborsthreatensGPSavailability,accuracyand (mostimportant)Integrity

WhileDigitalCommunica?onsandDigitalNaviga?on

aresuperficiallysimilar,therearesomefundamentaldifferencesthatmustbeunderstood…

13 GPS - Accuracy with Integrity

Summary: Potential Technical Issues and Solutions

March 2011 LightSquared Nationwide Interference with GPS 14

•  Maybefuturetechnicalsolu.onsgoodenoughtodiminish"leakage".(sensi.vityofGPSreceiverstotransmiaedpowerintheLightSquaredband.)

•  Suchsolu.onsnotimplementedincurrentGPSreceivers-somewillbeok,andmanyotherswillnot.

•  IncreasedfutureGPSreceiverCostandGPSaccuracydegrada.onsTBD

•  Secondissueistrespassing.(intrusionofLSQsignalsintotheGPSband.)•  FilteringLSQmodula2onmaytheore2callymakethistypeofinterferenceacceptable.•  Non-linearandothereffects("duc.ng")maynegatefiltereffec.veness•  Evalua.onrequiresrealdata-fromrealLSQtransmiaers.

•  allranges,azimuths,andeleva.ons.

•  Alsocityareaswherereflec.onscanreinforcesignalpower.

•  Thebigpoint:StoptherushtoLSQimplementa?on.Objec?velyevaluate:1.   TotalimpactoncurrentGPSreceivers2.   Impactofforcingsolu?onsonfutureGPSreceivers

•  NoDeploymentofLSQTransmi\ersun?lafullna?onaldialogiscomplete

Oncedeploymentisbegun,itwillbedifficulttoreverseit.Notethatwearehavingdifficultyininevenforcingareasonabledelaytoallowfullevalua?onofthesitua?on.