nationwide differential global positioning system (ndgps) nationwide differential global positioning...

Nationwide Differential Global Positioning System (NDGPS)

Nationwide DifferentialGlobal Positioning System

James A. ArnoldChairman

State and Local Government SubcommitteeCivil GPS Service Interface Committee

Presented to:Wyoming Regional Meeting

of theState and Local Government Subcommittee

of theCGSIC


Topics

• What is NDGPS?

• Where did NDGPS come from?

• Applications

• Status

• Research – HA-NDGPS


Differential GPS (DGPS)Differential GPS (DGPS)

MaximumMaximumRangeRange250 Miles250 Miles400 Km400 Km

ReferenceReferenceStationStation

.


The Coast Guard developed the DGPS service to providethe high accuracy needed for harbor and river navigation. USDOT is expanding it inland.


What does NDGPS give me? System Characteristics

• Accuracy– 0.5 meter near the reference

station

– Add 1 meter/150 Km

– Accuracy with Post Processing is 5 cm

• Integrity– 5 seconds at 100 bps

– 2.5 seconds at 200 bps


Why is Integrity Important?

Direction of Travel: West to East. GPS indicated positions jumped to SW West Virginia from 282345 to 2349Z Jul 01


Topics

• What is NDGPS?


• Applications

• Status



Interagency NDGPS Policy & Implementation Team

• Plans to expand the system for land users began in January 1997– Executive Steering Group – Policy & Implementation Team

Participants

DOT/OST Department of CommerceU.S. Coast Guard Department of InteriorFederal Highway Administration Department of AgricultureFederal Railroad Administration Army Corps of EngineersFederal Aviation Administration U.S. Air ForceEnvironmental Protection Agency Various States


Policy and Implementation TeamReport and Recommendation

• Coast Guard DGPS– Can be easily expanded

– Signal is not blocked by trees, hills, or buildings

– Meets most land and maritime needs when post processing techniques are used

• Executive Steering Group unanimously decided to expand the Coast Guard DGPS into a nationwide service


– Can be modified to provide high accuracy (better than 10 cm horizontal) in real time for surveying and land navigation needs

– Provided Funding in Coast Guard’s budget to implement NDGPS– Reuse Air Force Ground Wave Emergency Network (GWEN) equipment and sites

to augment installation of NDGPS– Integrate NDGPS into:

• Coast Guard’s DGPS for operational control• National Geodetic Survey’s Continuously Operated Reference Stations (CORS) service

for surveying applications• National Oceanic and Atmospheric Administration’s

Precipitable Water Vapor System for weather modeling– Ensure that the service is provided free

of any user fees– Continually upgrade the system– Sponsor new applications

Public Public LawLaw

Public Law 105-66Section 346

October 27, 1997


NDGPS Reference Station

EQUIPMENT AREA FORELECTRONIC EQUIPMENT

AND BACKUP POWERGROUP SHELTERS

TWIN 30 FOOT GPSREFERENCE STATION

RECEIVE ANTENNATOWERS 8 ft HIGH

FENCE

GRAVELACCESSROAD

4 FT HIGHFENCE

SITE AREA(700x700 FT)

GUY WIRES

12 TOP-LOADING ELEMENTS

299 FT TOWER

LF TRANSMITANTENNA

TOWER AREA

8 FT HIGH FENCE


299 foot299 footBeaconBeaconAntennaAntenna

Reference &Reference &IntegrityIntegrityAntennasAntennasTwo sets Two sets of eachof each

Converted GWEN to NDGPSAppleton, WA

DGPS EquipmentDGPS EquipmentShelterShelter

There is a similarThere is a similarshelter for the shelter for the 25KVA generator25KVA generator


International Standard• NDGPS is designed to an international, non-proprietary standard

– Compliant with RTCM SC-104 and ITU-R M.823

– Greatly increases market for manufacturers

– Significantly reduces receiver costs

• Signal is free to all users

• ~40 countries operate compatible systems

• Many other countries are planning systems

• Resulting in a seamless international navigation system


Acceptance of the international standardis leading to a seamless worldwide service.Acceptance of the international standard

is leading to a seamless worldwide service.


Topics

• What is NDGPS?


• Applications

• Status



NDGPS RequirementsPositive Train Control

• Provides Situational Awareness• Prevents accidents, saving over

$60 million per year• Reduces fuel consumption by

better pacing trains• Increases rail line capacity through closer

train spacing, thus reducing the need for additional capital investment in plant and equipment


Major Railroad Lines

A ubiquitous service with a high degree of accuracy & integrityis needed to improve railroad safety, efficiency & security.


Other Uses ofNationwide DGPS


Maritime Use

DGPS guides every type of craft fromsmall pleasure boats to large containerships


Army Corps of Engineers NDGPS in Dredging

Army Corps of EngineersNeeds 2 meter accuracy toPosition their dredging ships


NDGPS use inSurveying

GPS has revolutionized the surveying industry. NDGPS providessurvey grade accuracy when used in post processing applications.


Nationwide DGPSIntelligent Transportation System

•Save lives, increase safety, increase efficiency:

•Can provide improved GIS data•Reduced time to generate map•Improved accuracy.

•Can provide drivers with situational awareness, reducing accidents•Potential for improved fleet management without increased infrastructure costs.•Improves tracking of hazardous or valuable assets.


Hydrographic Surveys


NOAA’s Forecast Systems LabMeasuring Water Vapor

NDGPS Site in Whitney, NENDGPS Site in Whitney, NE

Water vapor is the most important component of weather and Water vapor is the most important component of weather and the least observed. NDGPS reference stations continuously the least observed. NDGPS reference stations continuously measure the water vapor in the atmosphere above the reference measure the water vapor in the atmosphere above the reference station, thus greatly improving short term weather forecasts. station, thus greatly improving short term weather forecasts.


U.S. Department ofAgriculture

• The Natural Resource Conservation Service in USDA has spent $7 M and purchased 5,000 NDGPS receivers

• USDA does not have enough federal employees to met requirements of the new farm bill

• They plan to outsource 5,700 Technical Service Provider positions. Many TSP positions will need NDGPS as well.


Benefits to Agriculture

• Mapping Soil quality

• Reducing use of pesticides and fertilizers

• Monitoring crop yield

NDGPS used in Precision NDGPS used in Precision Farming saves $5 to $14 per Farming saves $5 to $14 per acre.acre.


Alternative Farm Income

Photo and design courtesy of Franck Boynton, NAVTECH GPS


Nationwide DGPS Other Federal Agencies

• 24 Federal Agencies have Public Safety needs– EPA - Locating 1.4 million hazardous material & waste sites

– DOI (National Park Service) -

• Search and Rescue, fire fighting and oil spills

– DOE - Monitoring shipments of radioactive materials

– DOJ - Locating FBI & DEA personnel in danger & tracking vehicle location

– USDA - Fire fighting and resource management

– Bureau of Land Management - mapping natural resources and tracking fire fighting equipment

– USPS - tracking over 80,000 postal carriers


Nationwide DGPS State & Local Governments

• Many State & Local Governments needs • Mapping transportation infrastructure

• Responding to emergency 911 calls - Police, fire & ambulance

• Monitoring police officers’ safety

• Locating of fire hydrants in snow

• Monitoring contaminatedstream and well water

• Mapping & ManagingNatural Resources


University NAVSTARConsortium (UNAVCO)

• UNAVCO is a non-profit organization that promotes high-precision geodetic & strain techniques using GPS.

• Funded by NSF and NASA.• Uses dual-frequency GPS receivers to measure

Plate Rigidity, Plate Movement, Plate Deformation, Plate Boundary Zones to the millimeter level.

• NDGPS program has installed high stability antenna mounts & choke ring antennas at selected sites to meet UNAVCO needs.


Topics

• What is NDGPS?


• Applications

• Status



Sandy Hook, NJ

Key West, FL

Fort Stevens, OR

Pigeon Point, CA

Portsmouth Harbor, NH

Driver, VA

Cape Canaveral, FL

Louisville, KY

Cheboygan, MI

Cape Mendocino, CA

English Turn, LA

Moriches, NY

Galveston, TX

Wisconsin Point, WI

Milwaukee, WI

Upper Keweenaw, MI

Mobile Point, AL

Saginaw Bay, MI

Whidbey Island, WA

Point Loma, CA

Aransas Pass, TX

Topeka, KS

Neebish Island, MI

Memphis, TN

Egmont Key, FL

Vicksburg, MS

Brunswick, ME

Whitefish Point, MI

Detroit, MI

Millers Ferry, AL

Point Arguello, CA

Miami, FL

Sturgeon Bay, WI

Youngstown, NY

St. Louis, MO

Acushnet, MA

US COAST GUARD/ARMY CORPS OF ENGINEERS ANDPLANNED NATIONWIDE DIFFERENTIAL GPS SERVICE BROADCAST LOCATIONS

Goodland, KS

Ronan, MT

Penobscot, ME

Kirtland, NM

Appleton, WA

Macon, GA

Medora, ND

Edinburg, ND

Clark, SD

Whitney, NE

Austin, NV

Billings, MT

Flagstaff, AZ

Hudson Falls, NY

Pueblo, CO

Bakersfield, CA

Klamath Falls, OR

Hawk Run, PA

Hackleburg, AL

Spokane, WA

Savanna, GA

Myton, UT

Greensboro, NCKnoxville, TN

Cincinnati, OHMonterey, VA

Odessa, Tx

Munday, TX

Jackson, WY

El Paso, TX

Gooding, ID

Pine River, MN

Great Falls, MT

Summerfield, TX

Onondaga, MI

Medford, WI

Chico, CA

Fenner, CABobo, MS

Grady, AL

Rawlins, WY

Henrieville, UTHagerstown, MD

Martinsville, VA

Middlebury, VT

Jack Creek, NV

Tucson, AZ

Langtry, TX

St. Marys, WV

Hartsville, TN

Umiat Mount Chamberlain

Brooks RangeBaird MountainsRay Mountains Endicott MountainsAnderson

TananaGold Creek

Delta Junction

McGrath

Unalakleet

Pilot Point

Cold Bay

Kodiak

KenaiPotato Point

Cape HinchinbrookGustavus

Icy Cape

Annette Island

Lincoln, CA

Seneca, OR

Canton, OK

Fayetteville, AR

Pacific Junction, IA

Ledyard, IA

Annapolis, MD

Beaufort, NC

Kensington, SC

Iowa City, IA

Wenatchee, WA

Elmira, NY

Existing Coast Guard/USACE Sites

Green - OperatingRed - Planned

Nationwide Sites

Biorka Island

Kokole Point, HI

Upola Point, HI

Pahoa, HI


Milwaukee, WI

Topeka, KS

PLANNED NATIONWIDE DIFFERENTIAL GPS SERVICE BROADCAST LOCATIONS

Goodland, KS

Edinburg, ND

Bakersfield, CA

Klamath Falls, OR

Greensboro, NCKnoxville, TN

Cincinnati, OHMonterey, VA

Odessa, Tx

Munday, TX

Jackson, WY

El Paso, TX

Gooding, ID

Great Falls, MT

Onondaga, MI

Medford, WI

Fenner, CABobo, MS

Grady, AL

Rawlins, WY

Henrieville, UT

Martinsville, VA

Middlebury, VT

Jack Creek, NV

Tucson, AZ

Langtry, TX

St. Marys, WV

Seneca, OR

Canton, OK

Fayetteville, AR

Pacific Junction, IA

Ledyard, IAIowa City, IA

Wenatchee, WA

Elmira, NY

Existing Coast Guard/USACE Sites

Green - OperatingRed - Planned

Nationwide Sites

Austin, NV


NDGPS Coverage July 2003


Topics

• What is NDGPS?


• Applications

• Status



High Accuracy NDGPS ProgramBuilding a Nationwide Centimeter System


Program Objectives

• Enable 3-d dynamic positioning at the centimeter level throughout the NDGPS network

• Coexist with the current NDGPS broadcast

• Minimize the incremental cost of adding HA-NDGPS to NDGPS sites

• Utilize existing broadcast antenna, reference stations, and site infrastructure

• Incremental cost <$75K/ existing site


Broadcast Site Configuration

TRANSMITTER

DIPLEXER

REFERENCE

STATION

DATA

FORMATTERMODULATOR

TRANSMITTERDGPS/NDGPS

HIGH ACCURACYDGPS

TO ANTENNA

OBSERVABLES

CORRECTIONS

Rack Mount PC

DSP/Analog Card


High Accuracy NDGPS Applications

• Lane-keeping in land transportation applications• More accurate and efficient land, marine and

aerial surveying and mapping• Minimize vessel under-keel clearance and enable

autodocking in maritime applications• Precision agriculture• Machine control (Agriculture, Construction)• Snowplowing highways in whiteout conditions• Rail defect location and automated rail surveying


High Accuracy NDGPSR&D, Prototype, Standard

Development & Implementation

• The prototype High Accuracy NDGPS site operating in Hagerstown, MD, proves that 10 centimeter accuracy is achievable in real-time at ranges of 150 miles from the reference station

• R&D funding will investigate improvements in accuracy, integrity and overall signal robustness

• Finalize standard and implement at all 125 NDGPS sites (including original Coast Guard sites)


Accuracy of HA-NDGPS


Success Through Teamwork

Army CorpsArmy Corpsof Engineersof Engineers

Department Of Transportation

Federal RailroadAdministrationFederal RailroadAdministration

Department Of Transportation

Federal HighwayAdministrationFederal HighwayAdministration

Department of Interior

Bureau of LandManagement

nationwide differential global positioning system (ndgps) nationwide differential global positioning...

Documents

land users

coast guards dgps

seamless worldwide service

reference stationadd

implementation teamreport

coast guards budget

international standardis

post processing techniques