eloran’s ability to provide pnt and data in gps … and data in gps challenged environments ......

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eLoran’s Ability to Provide PNT and Data in GPS

Challenged Environments

UrsaNav & Johns Hopkins Applied Physics LaboratoryION Joint Navigation ConferenceJune 19, 2014

Imagination | Transformation | Innovation 2

Submarine primer (Los Angeles and Virginia Class)

The Problem: Reliance on Sole Means

The Need: Alternative PNT and D

The Solution: Co-Primary GPS and eLoran

eLoran Basics

The History: Clarinet Pilgrim

The Technology: Service Provider

The Technology: User

The Tipping Point: Time and Frequency

Latest Developments

Trial(s) Setups and Test Results

Possible Applications: P (w/ 2 or 3 XMTRS), F, UTC Synchronization, True Heading, and Data

Global eLoran Initiatives

A Way Forward in the U.S.?

Questions, and possibly answers.

ION JNC Outline

3

Ranging LORAN-C, sometimes termed Range-Range or Rho-Rho, was a development that extended LORAN-C into areas not covered by hyperbolic rates or into areas where the LOP intersections were of such shallow angles as to provide seriously degraded cross fixing. As one example, the hyperbolic formed by one pair along with the ranges observed from either master or slave or both provided useful geometry for navigation in areas with only one usable hyperbolic was normally available. In effect this geometry filled in the previously unusable areas out along the base line extensions. Ranging was dependent upon the availability of highly accurate atomic clocks to refine LORAN station accuracy and carry aboard ships. These provided a capability to synchronize the ship with the actual master and slave pulses so that the ship's receivers "knew" when the stations transmitted their signals. The time delays from the station's known time of transmission to the receipt at the ship formed a range circle that overlay hyperbolic LOPs or in themselves intersected to provide useful cross fixes.

EMEA OperationsBertem, Belgium

Corporate HeadquartersChesapeake, VA

Washington DC Metro AreaLeesburg, VA

Southeast RegionNorth Charleston, SCISO 9001

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The Problem: Vulnerabilities

The Need: Resilience

The Solution: Co-Primary GNSS and eLoran

eLoran Basics



The Tipping Point: Time and Frequency

Use Cases

Global eLoran Initiatives

A Way forward in the U.S.?

Questions, and possibly answers.

Outline





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The Problem

Vulnerabilities• Performance degradation

• Ionosphere & solar activities(natural)

• Unintentional & intentional(human factors)

• Signal blockage

• Spectrum competition

• Common signal use across GNSS

• Radio frequency interference

• System anomalies & failures

• Jamming

• Spoofing & Counterfeit Signals

• Proliferation of satellite systems

• Escalating costs

• Program funding delays

• Satellite launch problems

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

Blocker

Disrupter

Waterproof

40 Watts

All Bands

1,000 m

Of the 16 Critical Infrastructure / Key Resource sectors in

the U.S., 15 use GPS timing.

GPS timing is deemed essential

for 11 of the sectors.

[Source: U.S. DHS]

http://www.ctstechnologys.com/gps-jammers/986809.html













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The Problem: Intentional

Source: Ministry of Land Transport and

Maritime Affairs





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The Problem: Jamming

AIS

Depth Sounder Gyro Compass

Radar

DGPSECS

Nov / Dec 2009

Feb / Mar 2013

Source: GLAs





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The Problem: Spoofing

Sources: University of Texas at AustinDr. Todd Humphreys





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The Need: Resilience





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Hint: GNSS is vulnerable. eLoran is the best alternative.

Every Study and Report: Same Conclusion

US GAO

US GAO

US DOT US DOT US IAT US DOT US ndp

IMO IALA UK RAoE US DHSUK GLA





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Augmentation (vice primary)

SBAS (WAAS, EGNOS, MSAS), GBAS (DGPS)

Single mode

aviation, maritime, land-mobile, time, or frequency

Require external 1PPS or 10 MHz and/or Position

INS, Cs, Rb, CSAC, OCXO

Similar failure modes (e.g., low power, shared spectrum)

GNSS, communications satellites

Over-promised capability and often coupled to GNSS

NTP, PTP (IEEE-1588), fiber

Local area

radio, TV, WiFi

Unprotected spectrum

ISM band

Not under government control

StarFire, OnStar

Not under (fill in your country’s) sovereign control

GPS, GLONASS, CNSS, Galileo

Regional

QZSS, IRNSS

Many years away

MEMS INS, cold atom, gravimetric

National or regional

ASTRA, Sky, Viasat, Skylife, Direct TV, Dish

Why Alternatives are NOT Co-Primary





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GNSS + eLoran: The Best Co-Primary Solutions

Diverse failure modes

Complementary

Interoperable

Independent

Multi-Modal

Wide Area

CO-PRIMARY SOLUTIONS GNSS 1 Enhanced Loran

Frequency 1.X GHz (Various) 100 kHz

Power Very Low ~ 1.3 M times larger

Signal Changes Hard / Expensive Quick / Inexpensive

Modulation Changes Hard / Expensive Quick / Inexpensive

Global Yes Wide Area / Regional

Complementary & Interoperable Yes Yes

(C/A) Jamming Resistence Low High

Spoofing Resistence Low High

Interference Detection & Mitigation 2 No Yes

Proof of Time 3 No Yes

Proof of Position 3 No Yes

Maritime: HEA, CCZ, EEZ Yes Yes

Aviation: En-Route 4 Yes Yes

Aviation: Terminal 4 Yes Yes

Aviation: Non-Precision Approach 4 Yes Yes

Aviation: Precision Approach Yes No

Frequency 4 Stratum-1 Stratum-1

UTC (1PPS) 2 Yes Yes

Precise Time 4 Yes Yes

Land Mobile 2 Yes Yes

Location Based Yes Yes

3D (altitude) Yes With Altimeter

Data Channel No Yes

Third-Party Data Channel(s) No Yes

Integrity Via Augmentation(s) / RAIM Built In

Indoors Depends Yes

Urban Canyons Depends Yes

Triple Canopy No Yes

Underground No Yes

Under Water No Salt Water Depth Limited

Mountainous Terrain Depends Yes

Notes: 1 Specifically civilian GPS;

2 Courtesy of Professor Last;

3 Courtesy of Logan Scott;

4 U.S. FAA

OPERATIONS

RESILIENCE

MODES

ADDITIONAL ATTRIBUTES

P

T

N

Chemical

Commercial Facilities

Communications

Critical Manufacturing

Dams

Defense Industrial Base

Emergency Services

Energy

GPS

Financial Services

Food and Agriculture

Government Facilities

Healthcare

Information Technology

Nuclear Systems

Transportation Systems

Water Systems

eLoran

Critical Infrastructure / Key Resource SectorsSource: US PPD-21 of February 12, 2013





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eLoran Basics

Key characteristics

• High power (typically > 250 kW)

• Low frequency (100 kHz)

• Pulse shaped signals allow groundwave- skywave separation

• Data channel to provide UTCinformation, Differential corrections andintegrity information

• Long range (>1,000 miles) coverage

• No common failure modes with GNSS

• Provides the same information as GNSS (time, frequency, position) PLUS data and integrity

• Transmissions synchronized to UTC

10 ms

3 kmUTC Sync

Point





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Standard Loran (Loran-C)

Stand alone Loran-C. Offset 357.3 m. Error of 7.1 m (95%) from surveyed position.





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GPS

Single frequency GPS. Offset 0.6 m (2 feet). Error 2.2m (95%) from surveyed position.





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Enhanced Loran (eLoran)

eLoran. Offset 2.4 m (< 8 feet). Error 7.1 m (95%) from surveyed position.





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Transmitting Site

1

2

3

4

5

6

230 VUPS

LAN

Uninterruptible Power Supply - provided by GLAs

Server

Network switch with VPN support

MCS Server

WorkstationSecondary Workstation

LCD, keyboard and mouse set

per MCS Workstation

WorkstationPrimary Workstation“Control” &Monitor Site

Differential eLoran Site





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“Software Defined” Receivers• Multi-mode• E- or H-Field Antennas

Availability• Timing and Frequency• Maritime• Differential (ΔLoran) Reference Sites• Scientific, Research• Land Mobile• OEM Module• Aviation






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eLoran in Europe

• eLoran 1PPS measured against

Novatel OEM3 GPS Receiver

• 6-day continuous observation.

• 120 seconds observation interval

• Diurnal behavior present but less

prominent.

• Standard deviation – 14 ns

• 480 km (298 miles) from transmitter

at Lessay, France

696 km

480 km





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Use Case: Telecommunications Timing

ETSI PRC Mask

UN-150 eLoran

performance

TS3100 GPS

PRS

performance

Testing by Chronos Technology Ltd.Additional Testing by National Physical Laboratory





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• Contract awarded in 2013 for 7 differential Loran sites

• General Lighthouse Authorities active in standardization efforts

Global Initiatives: UK





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Predicted Accuracy of RoK eLoran System

Assignment of dLoran Reference Stations

International Tender in Process

Global Initiatives : RoK





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• Loran-C System implemented in 1980s

• Extensive use by U.S. DoD in Desert Storm in 1991

• Eurofix Data Channel added in 2004

• Control System Upgrade in 2007

• Tendered for Prototype eLoran Receiver in 2012

• Finalizing eLoran Upgrade Tender for expected release in 2014

Global Initiatives: KSA





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India Coverage Example using

11 eLoran Stations

-Station locations indicated by

circles

-Inner contour is eLoran navigation

coverage area capable of providing

maritime <20m accuracy using

dLoran reference stations

-Outer contour is time and data

service area

Note: Coverage area is approximated and is shown for

illustration purposes only

Project is past budget stage, inPre-Tender Technical Design

Global Initiatives: India





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Global Initiatives: Russia and Iran





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• Possible Approach

– Government loans existing assets (i.e. land, buildings, antennas, site equipment)

under a 20 year lease

– Industry provides necessary equipment and services to fulfill a service-level

agreement (similar to GLAs in the UK)

– Potential for a two-tiered service with mechanism for revenue recovery to reduce

or eliminate out-year costs to government

• Phased Approach

– Initial phase resurrects 2008 era

– Rapid build out of CONUS high reliability timing network (dual coverage)

– Position and Navigation capabilities added later

– Encourage Canadian interest/investment along US / CAN border

– Expand into Alaska, Hawaii, Puerto Rico

• Benefits

– Deferral of Environmental Compliance & Restoration costs

– Fulfills backup PNT capabilities per National Security Presidential Directives

– Advances technology and creates employment

USA: Public Private Partnership?





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Start: 4 Station (“Single”) Timing Coverage





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19 Station Timing Coverage





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19 Station Position and Navigation





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QUESTIONS?

eloran’s ability to provide pnt and data in gps … and data in gps challenged environments ......

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