Coherent Navigation Stanford PNT Symposium 2009

Copyright © 2007 Boeing. All rights reserved.

Copyright © 2009 Coherent Navigation, Inc. All rights reserved.

Stanford PNT Symposium 2009 Coherent Navigation




Coherent Navigation Global Navigation and Communication Solutions

We pioneer advanced positioning, navigation, timing, and communication (PNT+C) solutions for government and civilian market.

We employ GPS/GNSS, Iridium, and other satellite signals.

We develop products with greatly improved navigation accuracy, availability, integrity, and jam resistance.

We integrate solutions with global two-way communications for enhanced utility and security.

Founded in 2008 by GPS and satellite systems experts from Stanford and Cornell Universities. 8 employees at 4 sites (San Mateo CA, Washington DC, Ithaca NY, Austin TX).

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Copyright © 2007 Boeing. All rights reserved. \



Outline

Introduction to iGPS

Navy High-Integrity GPS Program

Potential Applications

Coherent Navigation Security and Integrity R&D

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Y Copyright © 2009 Coherent Navigation, Inc. All rights reserved.


iGPS: A System of Systems LEO-MEO Satellite Hybrid

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Enhancement to Existing Nav Performance

• Accuracy • Integrity • Acquisition Time • Availability, Global Coverage • Integrated Nav-Com • Precision Time Transfer • Interference Rejection

Short Schedule

• Capability Available in 2010

Low Cost

• Leverages existing assets

EXISTING IRIDIUM SPACECRAFT

EXISTING GPS SPACECRAFT

Orbits are Shown to Scale

Reference Network

Satellite Network Operations Center

EXISTING IRIDIUM GROUND INFRASTRUCTURE

GPS Master Control Station

EXISTING GPS GROUND INFRASTRUCTURE

Immediate iGPS Benefits

Boeing has been leading the

development of proprietary iGPS

as an enhancement to GPS.




The Iridium Satellite Constellation

Constellation Size: 66 Satellites Orbit: 780 km, near polar, 6 planes Primary Purpose: Global, Micro-Aperture Communication User Base:

Military, Civil, and Commercial 328,000 subscribers as of Q1 2009

“Iridium NEXT” repopulation preparation underway Iridium raised $400M gross proceeds led by Greenhill & Co. Financing completed September 23, 2009. Iridium now trading publicly on NASDAQ.

Physical Attributes

Spatial Diversity 1-3+ satellites in view LEO High Doppler/Rapid Geometry Change

Built-in Comm & Datalink Global Backbone Higher power transmitter

Defeats jamming of aiding signal Frequency near GPS L1

Can share same antenna


BOEINGCopyright © 2009 Coherent Navigation, Inc. All rights reserved.


iGPS Builds on Transit Heritage

iGPS leverages both Transit and GPS Heritage: Low Earth Orbit Provides

Rapid Angle Motion and Spatial Diversity for a Geometry-Rich Solution

SV Footprint

User Position Error Upon LEO Acquisition

(bracketed by Doppler uncertainty at two

separate epochs)

Initial LEO Position

LEO Position after ~100 sec

Contours of Constant Range Rate

LEO Orbit Plane Trace

1962: Transit

2009: iGPS

• U.S. Transit Navigation Satellites provided 500 m Navigation Error.

• Performance limited in part by onboard clock error.

• Iridium + Ground Reference Network creates GPS quality clock in the user equipment


BOEINGCopyright © 2009 Coherent Navigation, Inc. All rights reserved.


IONOSPHERE

TROPOSPHERE

Time Stability Transfer for Jam Resistance

GPS

Reference Monitor

Network

Iridium

Single-Frequency

Ranging and Data Downlink

Data collected May 31, 2007 Detrended Error is 20 ps RMS

Demonstrated Time Stability Transfer between Philadelphia and Cedar Rapids

(~1,400 km)

Det

rend

ed ti

me

trans

fer e

rror

(cm

)

High-power Time Stability

Transfer feedforward via Iridium

enables User to coherently filter

out GPS interference

User

High-stability Reference clock,

synched to GPS

Low-cost native clock + Iridium carrier phase tracking + reference network corrections =

Synthesized high stability local clock

Iridium K-band cross links


BCopyright © 2009 Coherent Navigation, Inc. All rights reserved.


Real-Time Dynamic Tracking in the Presence of Interference

Right “Truth”

Antenna Left

“Truth” Antenna

iGPS Solution (MEMS IMU)

iGPS Achieves High Accuracy under Dynamics AND Interference

iGPS

White Noise Interference was Introduced via Coaxial Cable

10 cm radius circle shown for accuracy reference

Reference Station




Outline





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iGPS – Initial Focus on Anti-Jam Performance

Boeing has developed proprietary iGPS as an enhancement to GPS

Technology heritage includes

FAA-funded GPS autoland research at Stanford University (accuracy and integrity) Navy/Boeing X-31 program based on IntegriNautics (now Novariant) IBLS Landing System 2001-2007 Boeing IR&D and patents emphasizing GPS anti-jam applications

DoD sponsoring iGPS military applications, transitionable to operations

iGPS program funded by Naval Research Laboratory (NRL) in Washington, DC Boeing is prime contractor for $153.5M program spanning 2008-2011 Team includes Iridium Communications, Rockwell Collins, and Coherent Navigation

iGPS offers the opportunity to retrofit a subset of 300,000 existing

DAGRs with additional jamming resistance without a H/W change




Selected iGPS Accomplishments to Date

iGPS anti-jam capabilities tested in 2007

Enhanced PNT Anti-Jam capability based on carrier phase Long baseline time stability transfer proof of concept

iGPS time synchronization demonstrated in 2008

iGPS enables access to GPS time during GPS denial of service

Global fielding of Enhanced Narrowband (ENB) waveform in 2009

Software modification to Iridium satellite computers, enabling second-generation GPS aiding signals to be broadcast anywhere in the world on demand.

Iridium SVs (at LEO)

GPS SVs (at MEO)

Demonstrated GPS PNT cold start under jamming and dynamics in 2009

Vehicle-mounted demonstrator acquired within minutes Yielded significant improvement over GPS alone


BORY Copyright © 2009 Coherent Navigation, Inc. All rights reserved.


New “Tethered” Upgrade Path for Existing GPS Hardware

Original program scope added iGPS components to DAGR design Embedded GPS P-code generator innovation synchronizes clocks w/o H/W impact Full iGPS performance can be added to existing GPS with only S/W modification

iGPS

Module

Existing Serial

Interface

Existing ExternalAntenna

Input

Existing DAGR plus upgraded software

L band Antenna

iGPS Module interfaces with existing deployed GPS Receivers

requiring only a Software Modification

This invention was made with Government support under Navy Contract N00173-08-C-2074 awarded by the Naval Research Laboratory. The Government has certain rights in the invention.

COHERENT NAVIGATION PATENT PENDING





Outline





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BOCopyright © 2009 Coherent Navigation, Inc. All rights reserved.


How iGPS Provides Rapid Accuracy and Integrity

String of Distinct SV Lines-of-Sight due to Rapid Angular Motion of LEO Satellite

LEO Satellite Trajectory LEO Satellite Locations by Epoch

Consistent Range Measurements Assuming Proper Bias

Inconsistent (Null) Solution Assuming Improper Ranging Bias

True User Location

iGPS Offers High Accuracy AND Integrity via Scores of Virtual Satellites

Local section of Iridium orbit sphere Zenith

User position

Position Covariance after single pass (small axis is accurate to ~1 cm)

Synthetic Aperture formed by Spacecraft Trajectory

Ordinary 3D Kinematic GPS Provides Relative Position and Time LEO Motion Enables Resolution of the absolute user position and LEO Bias This is a carrier-only solution—code helps, but is not explicitly required.


BOECopyright © 2009 Coherent Navigation, Inc. All rights reserved.


Near Future

iGPS Applied to Lowering Aircraft Landing Minima Combined FF-SSF Availability

Reference configuration (near-future): Single-frequency user, using WAAS-like ground

corrections (TF=8min). Results promising for longer-term

improvements:

Dual-frequency (fewer reference stations)

Availability

Dual frequency GPS & Iridium Dual frequency GPS

10 m Vertical Alert Limit

Mathieu Joerger, Jason Neale and Boris Pervan , “Iridium/GPS Carrier Phase Positioning and Fault Detection Over Wide Areas”,

ION GNSS 2009 – Savannah, GA, September 24, 2009.




Outline





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Understanding the Threat of GPS Spoofing

DOT Volpe report (2001) endorsed research into the practicality of GPS spoofing. As academics, current CN team members Ledvina and Humphreys developed GPS spoofing testbed.

Goal: Research spoofing detection and countermeasure strategies. Result: Demonstrated innovative detection schemes.

At Coherent Navigation, research has expanded to applications of this technology.

GPS World

March 2009

Jan 2009

Notional Spoofing Attack


RY Copyright © 2009 Coherent Navigation, Inc. All rights reserved.


The GPS Assimilator extends & protects existing equipment

The GPS Assimilator can modernize and can implement jamming/

spoofing countermeasures without requiring hardware or software changes to installed or legacy equipment.



GPS

ICD-200

compliant

Synthesized

RF signals


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GPS Assimilator Prototype

Flexible software-defined radio platform enables

GPS Assimilator and spoofing countermeasures R&D



Digital signal processing implemented in C++ on a high-end DSP Capabilities:

12 L1 C/A & 10 L2C tracking channels 8 L1 C/A simulation channels 1 Hz navigation solution Acquisition in background


BCopyright © 2009 Coherent Navigation, Inc. All rights reserved.



iGPS has potential to provide significant interference rejection to Military applications with initial operations commencing next year.

With near-term, cost effective performance enhancements in PNT accuracy, integrity, and availability, the potential for iGPS appears to be broad.

The iGPS infrastructure provides an experimental testbed for a broad range of innovative global integrated Nav-Com capability going forward.

Coherent Navigation, in the spirit of the Silicon Valley “garage”, is excited to be an innovative force in improving the utility and security of GPS.




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The Coherent Navigation team gratefully acknowledges the support of:

Mr. Jay Oaks, iGPS Program Manager, US Naval Research Laboratory The Boeing Company




Contact information:

Coherent Navigation, Inc. 1500 Fashion Island Blvd #105 San Mateo, CA 94404 [email protected]

Clark Cohen, PhD. CEO [email protected] William Bencze, PhD. COO [email protected] Brent Ledvina, PhD. Dir. Business Development [email protected]

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Coherent Navigation Stanford PNT Symposium 2009

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