Train Location Validation Against GPS/GNSS Spoofing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing train control systems are vulnerable to GPS/GNSS signal spoofing and jamming, which can lead to inaccurate train location determination, posing safety risks.

Innovation Solution

A system that validates train location by comparing GPS/GNSS data with independently calculated expected location data, using departure and arrival times, and raises alarms for discrepancies, employing a software module in the Railway Control Centre to detect and mitigate spoofing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If GPS/GNSS signals are used to determine train location, then location determination capability is improved, but vulnerability to spoofing and jamming increases

Engineering Contradiction:
Improvetrain location determinationVSAvoidsignal validity
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent introduces an intermediary validation system that acts as a mediator between the GPS/GNSS receiver and the train control system. This validation system cross-checks reported location data against independently calculated expected location data derived from timetable information, thereby filtering out spoofed or jammed signals without eliminating the beneficial use of GPS/GNSS for location determination.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The system implements a feedback mechanism where the validation system continuously monitors the consistency between reported location data and expected location data based on timetable information. When discrepancies are detected, the system provides feedback to reject the erroneous GPS/GNSS data, creating a closed-loop control that maintains reliability while preserving measurement precision.

Inventive Principle:
Principle #23Feedback

2Reliability

If validation system is added to detect spoofing, then reliability is improved, but system complexity increases

Engineering Contradiction:
Improvelocation data validityVSAvoidvalidation system
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The validation system creates a copy of the expected location data by independently calculating train position based on timetable information and comparing it with the reported GPS/GNSS location. This copying approach provides validation without requiring complex additional hardware, as it uses software-based calculation and comparison of location coordinates.

Inventive Principle:
Principle #26Copying

3Measurement precision

If expected location data calculation is performed continuously, then detection accuracy is improved, but computational load increases

Engineering Contradiction:
Improvelocation verification accuracyVSAvoidcomputational energy
Core Design Contradiction:
Measurement precisionVSUse of energy by moving object

Solution Approach 1:

The validation system performs expected location data calculation periodically at scheduled intervals rather than continuously. It calculates expected location at validation points along the route and compares these with reported location data received at corresponding times, reducing computational energy consumption while maintaining sufficient detection accuracy for safety-critical applications.

Inventive Principle:
Principle #19Periodic action

Data Source

PatentEP3925853B1A system and method for detecting erroneous location data reported by a train
Publication Date: 2025.10.15 SIEMENS MOBILITY LTD
  • EP3925853B1 patent drawingFigure 1
  • EP3925853B1 patent drawingFigure 2
  • EP3925853B1 patent drawingFigure 3

AI summary

A system and method for detecting erroneous location data reported by a train.