STRIDEIntroductionIntroduction
Increasing use for PNT applications:
PositioningNavigationTiming
STRIDEGNSS Vulnerabilities GNSS Vulnerabilities
Ionospheric delayTropospheric delaySatellite clock errorEphemeris errorSignal error
LOS blockageReceiver noiseDilution of precisionJammingSpoofing
STRIDEGNSS SpoofingGNSS Spoofing
Forging and transmission of navigation messages in order to manipulate the navigation solutions of GNSS receivers
Even if a spoofer is not fully successful, he/she can still create significant errors and jam GNSS signals over large areas
STRIDEGNSS SpoofingGNSS Spoofing
GPS spoofing used to trick a British vessel into Chinese waters
STRIDEGNSS SpoofingGNSS Spoofing
STRIDEGNSS SpoofingGNSS Spoofing
STRIDEGNSS SpoofingGNSS Spoofing
STRIDEGNSS SpoofingGNSS Spoofing
A number of GNSS simulators have been designed for legal purposes
In the wrong hands, can be used for spoofing
STRIDEGNSS SpoofingGNSS Spoofing
GNSS simulators can be built with relatively low cost equipment
STRIDEGNSS SpoofingGNSS Spoofing
The spoofing threat continuum
STRIDEGNSS SpoofingGNSS Spoofing
Meaconing
GNSS record and playback systems record real GNSS signals and retransmit the signals to evaluated GNSS receivers.
While spoofing using this method cannot be used to impose user-defined scenarios on a receiver, it can still cause the receiver to compute false location fixes using the transmitted real GNSS signals.
Furthermore, this form of attack can be used for spoofing military GNSS signals
STRIDEGNSS SpoofingGNSS Spoofing
STRIDEGNSS SpoofingGNSS Spoofing
STRIDEObjectivesObjectives
This study is aimed at evaluating GPS performance during simplistic GPS spoofing attacks.
Spoofing is conducted using a standalone GPS simulator, which at present poses the greatest near-term threat.
In this type of spoofing attack, the spoofing signal is not synchronised (in terms of power level, phase, Doppler shift and data content) with the genuine signals received by the target GPS receiver.
This could cause the target GPS receiver to temporarily lose position fix lock first, before being taken over by the spoofing signal.
STRIDEMethodologyMethodology
Test Setup
Test area located at N 2º 58.056’ E 101º 48.586’ 70m
STRIDEMethodologyMethodologyTest Scenario
• Test area located at N 2º 58.056’ E 101º 48.586’ 70m• The spoofing signal is set for position of N 2º 58’ E 101º 48’ 80m,
while the time is set at the simulator’s GPS receiver’s time.
STRIDEResults & DiscussionResults & Discussion
The effect of GPS spoofing attacks
Evaluated GPS receiver
Reference GPS receiver
STRIDEResults & DiscussionResults & Discussion
Reading 1 Reading 2 Reading 3
Evaluated GPS receiver
The effect of spoofing on GPS accuracy
Reading 4 Reading 5 Reading 6
STRIDEResults & DiscussionResults & Discussion
Reading 1 Reading 2 Reading 3
Reference GPS receiver
The effect of spoofing on GPS accuracy
Reading 4 Reading 5 Reading 6
STRIDEGPS SpoofingGPS Spoofing
The effect of spoofing on GPS accuracy
Evaluated GPS receiver Reference GPS receiver
STRIDEConclusionConclusion
Varying minimum spoofing signal power levels, times between position fix lost and spoofing, and probable error patterns are observed for different dates and times.
This is due to the GPS satellite constellation being dynamic, causing varying GPS satellite geometry over time, resulting in GPS performance being time dependent.
Variation in other GNSS error parameters, including ionospheric and tropospheric delays, satellite clock, ephemeris and multipath errors, and unintentional signal interferences and obstructions, could have also resulted in the variation of GPS performance.
As the spoofing signal power level is increased, probable error values increase due to decreasing C/N0levels for GPS satellites tracked by the receiver.
For all the readings, the highest probable errors occur at the minimum spoofing power levels. After spoofing takes place, the probable errors reduce to levels that are lower as compared to prior to transmission of the spoofing signal.
This occurs as at this point, the spoofing signal power level is relatively large, resulting in high C/N0 level and hence, improved accuracy.
STRIDEScope for Future WorkScope for Future Work
On the whole, this study has demonstrated the disadvantages of field GNSS evaluations.
Without the ability to control the various GNSS error parameters, it is difficult to effectively study the effect of any particular error parameter, in the case of this study, spoofing, on GNSS accuracy.
This highlights the importance of conducting such tests in a controlled environment, using a GNSS simulator as the source of genuine GNSS signals as opposed to live GNSS signals.
This would allow the tests to be conducted under repeatable user-controlled conditions.
STRIDEGNSS Receiver EvaluationGNSS Receiver Evaluation
Employs live GNSS signals. Should be conducted in open area with
clear view of the sky. Tests scenarios are uncontrollable by
users and not repeatable.
Field Evaluation
Employs simulated GNSS signals. Should be conducted in a RF enclosure
(e.g. anechoic chamber). Test scenarios are user controllable
and repeatable.
GNSS Simulation
STRIDEGPS JammingGPS Jamming
Field Evaluation GPS Simulation
STRIDEGPS Functional TestsGPS Functional Tests
Pendulum Instruments GPS-12R
Topcon Hiper GA
Magellan Z-Max
Trimble R8
Trimble Geoexplorer 6000 GeoXH, Nomad
900G and Juno SB
ProMark 200
STRIDEResearch CollaborationsResearch Collaborations
Effect of Radio Frequency Interference (RFI) on Global Positioning System (GPS) Static Observations
Collaboration with Faculty of Architecture, Planning and Surveying (FSPU), Universiti Teknologi MARA (UiTM)
Project Co-Leaders: Assoc. Prof. Sr. Dr. Azman
Mohd Suldi Mr. Ahmad Norhisyam Idris