wide area timing, frequency, & data using lf technologytprop = tprop_1 + tprop_2 (via lf data...

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Charles Schue Stanford University PNT Challenges and Opportuni:es Symposium November 2012 Wide Area Timing, Frequency, & Data Using LF Technology

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Page 1: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

CharlesSchue

StanfordUniversityPNTChallengesandOpportuni:esSymposiumNovember2012

WideAreaTiming,Frequency,&DataUsingLFTechnology

Page 2: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

P

T

N

F

Food&Agriculture

CommercialFacili=es

Dams EnergyInforma=onTechnology

Healthcare&PublicHealth

Banking&Finance

Communica=ons

DefenseIndustrialBase

GovernmentFacili=es

Monuments&Icons

Transporta=onSystems

ChemicalCri=calManufacturing

EmergencyServices

Postal&Shipping

NuclearSystems

Water

2

Page 3: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Concerns• Solesource• Funding• Constella=onsize• Constella=onage

Vulnerabili=es• Signalblockage• Jamming• Performancedegrada=on• Natural• Human(Uninten=onal/Inten=onal)

• Spectrumcompe==on(e.g.,LSQ)• Radiofrequencyinterference• Spoofing&CounterfeitSignals

Whybeconcerned?

Of the (18) CIKR sectors, (15) use GPS

timing.

GPS timing is deemed essential

for (11) of the sectors.

[Source: DHS]

[Source: ctstechnologys.com/gps-jammers/]

Blocker

Disrupter

Waterproof

40 Watts

All Bands

1,000 m

3

Page 4: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Tested&Approved• Government(s)• Academia• Industry• Users

TechnologyAvailableToday• TransmiWers• TransmitAntennae• Receivers• ReceiveAntennae• Command,Control,Communica=ons

Whatifwehadasolu=on?

Anti-Jam Anti-Spoof Anti-Cyber Proof-of-Position Proof-of-Time

Indoors Urban Canyons Mountains Triple Canopy Northern Latitudes Underground Under water Under ice

Accuracy Availability

Integrity Continuity

Complementary Interoperable

Wide Area Multi-modal

P, N, T, F + D, I

4

Page 5: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Wecallthatsolu=onLF...

Loran‐C

eLoran eLoran

eLoran LFPhoenix™ LFPhoenix™

LFPhoenix™ will operate in ‘compatibility mode’

Full LFPhoenix™ potential

5

Page 6: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

P

T

N

F

Food&Agriculture

CommercialFacili=es

Dams EnergyInforma=onTechnology

Healthcare&PublicHealth

Banking&Finance

Communica=ons

DefenseIndustrialBase

GovernmentFacili=es

Monuments&Icons

Transporta=onSystems

ChemicalCri=calManufacturing

EmergencyServices

Postal&Shipping

NuclearSystems

Water

6

Page 7: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Equivalentsystems…diverseTechnologies.

7

Page 8: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

EquivalentWidearea,mul=‐modal,withsimilarA.A.I.C,andbuilt‐inintegrity.

Provides• Resilience• Robustness• Alterna=ve• Backup

LFasaSensor

LFasa

Sensor

8

Page 9: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Infrastructure1960’sto2000’s.

LargeSWAP‐C• Logis=cs• Maintenance• Personnel• Training• Installa=on

Yesterday

9

Page 10: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Infrastructure21stcentury.

VerySmallSWAP‐C• Smallfootprint• Autonomous• Efficient• Unmanned• Future‐proof

TodayandTomorrow

10

Page 11: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Timing&ControlCoordinatedTimeScale,transmiWerI/F,C3,signalanalysis.

Capabili=es• nsUTCsynchroniza=on

• GNSS/RNSS• TWSTTorTWLFTT

• Mul=‐modemonitorreceiver(s)• LFDataChannel(s)• Advancedmodula=on,signals,waveforms

TechnologyExistsToday 10.5’

11

Page 12: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

TransmiWersState‐of‐the‐art;highperformance;patentpendingpowerrecovery.

NautelNLSeries• VerysmallSWAP• >75%efficient• Self‐healing;hot‐swappable• (e)Loran,(e)Chayka• LFPhoenix™advancedmodula=on,signals,waveforms

TechnologyExistsToday 10.5’

12

Page 13: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

“eLoran‐in‐a‐Box”“Triple‐T”:Temporary,Tac=cal,orTransportable.

FieldTested• 4‐6hourssetup• ~125NMrange• Dual‐ratedw/LDC• 70’x70’x70’InvertedPyramid• Subs=tutedRydertruckforCONEX

TechnologyExistsToday

Equipment Truck

Telescoping Antenna Supports

Antenna Tuning Unit

13

Page 14: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

ReceiversMul=‐mode“SDRs”for(e)Loran,(e)Chayka,andLFPhoenix™.

Horizon1Markets• dLoranReference• Time,Timing,&Frequency• OEM(Mi#gator™shownatright)• Scien=fic,research,ASFsurvey• Mari=me

TechnologyExistsToday

14

Page 15: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

ReceiveAntennaeEvolvingtoreduceSWAP‐C.

E‐andH‐Field• Indoor• Time,Timing,&Frequency• dLoranReference• Mari=me• Scien=fic,research,ASFsurvey• (e)Loran,(e)Chayka,LFPhoenix™

TechnologyExistsToday

1.5” x 1.5” x .75”

E‐Field

H‐Field

6” x 6” x 2”

15

Page 16: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Coopera=vePromotesR&D,TechnologyTransfer.

Evaluate• Widearea=metransfer• IndoorT,F,&Drecovery• ImprovedalignmenttoUTC• PerformanceasinputtoCIKR• Advancedwaveforms&signals• Advancedmodula=ontechniques

TheCRADA

16

Page 17: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

CRADA:EarlyResults

17

Page 18: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

LFPhoenix™1.2kWERP226kmdistance

IndoorTests• Firstblush• Uncontrolledenvironment• H‐Fieldantennae

EarlyTimingResults

18

Page 19: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

IndoorTimingTrials

  6” x 6” x 2” H-Field   Receiver set for 1 second integration   1-sigma value: 3.42 ns (raw measurements)

  1.5” x 1.5” x .75” H-Field   Receiver set for 32 seconds integration   1-sigma value: 112.76 (raw measurements)

19

Page 20: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

CRADA:NextUp

Receiver can determine:

Tprop = Tprop_1 + Tprop_2 (via LF data channel message)

ΔT = Tprop_1 – Tprop_2 (via direct measurement)

Tprop_1 and Tprop_2 can be solved independent of ASF values (!)

Receiver can recover time w/o offsets due to propagation:

When receiver is on the baseline between transmitters

Under the assumption that propagation is a linear phenomenon

Applies to eLoran and LFPhoenix™ techniques we have tried so far

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Page 21: Wide Area Timing, Frequency, & Data Using LF TechnologyTprop = Tprop_1 + Tprop_2 (via LF data channel message) ΔT = Tprop_1 – Tprop_2 (via direct measurement) Tprop_1 and Tprop_2

Safeguardingourcri=calInfrastructure

GPS+LF