Vehicle Locking System Interference Filter

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Solution Overview

Problem

Electronic locking systems for vehicles are susceptible to interference in electromagnetic signal transmission, leading to unauthorized access or driving authorization denial, particularly in electric and hybrid vehicles during low-frequency interference events.

Innovation Solution

Incorporating a filter in the locking system that can be switched on to reduce and suppress interference, with the filter located in the second device to prevent interference frequencies from coupling, and using inductive signals for wake-up and area delimitation and radio signals for authentication, allowing for efficient operation and increased security.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a filter is permanently activated to suppress interference, then reliability is improved, but energy consumption increases and battery life decreases

Engineering Contradiction:
Improveoperational reliabilityVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The filter is implemented as a dynamically switchable component rather than a permanently active element. The control device monitors interference levels in the electromagnetic environment and activates the filter only when interference exceeds a predetermined threshold, thereby adapting the system's interference suppression capability to actual environmental conditions and optimizing energy consumption.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system performs periodic interference level measurements and activates the filter in periodic intervals when needed. Instead of continuous operation, the filter is switched on temporarily during interference events and switched off when the environment is clean, creating a periodic on-off pattern that maintains reliability while reducing overall energy consumption.

Inventive Principle:
Principle #19Periodic action

2Reliability

If signal transmission is performed continuously to ensure authorization, then reliability is improved, but energy consumption increases

Engineering Contradiction:
Improveauthorization reliabilityVSAvoidbattery energy
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The second device transitions from continuous signal transmission to periodic transmission, activating only during authorized time windows when the control device is expecting authentication signals. This periodic transmission pattern maintains authorization reliability while dramatically reducing energy consumption during idle periods.

Inventive Principle:
Principle #19Periodic action

Solution Approach 2:

The control device performs preliminary actions by sending wake-up signals and authorization requests before the second device needs to transmit. This allows the second device to remain in low-power mode longer and only activate transmission when explicitly requested, improving energy efficiency while maintaining reliable authorization.

Inventive Principle:
Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

Enhances operational reliability and battery life by reducing interference, enabling robust operation even under low-frequency interference conditions, such as during inductive charging, and preventing unauthorized access.

Implementation Method 1

a filter for reducing and/or suppressing interference is provided in the first device and/or in the second device

Methodology Applied
Scientific EffectElectromagnetic filtering: Filter (electronic)

Implementation Method 2

use an inductive signal for the wake-up signal and/or for the area delimitation signal

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP3310627B1Locking system for a vehicle
Publication Date: 2019.01.30 MARQUARDT GMBH
  • EP3310627B1 patent drawingFigure 1
  • EP3310627B1 patent drawingFigure 2
  • EP3310627B1 patent drawingFigure 3

AI summary

The invention relates to a locking system (3), especially for providing authorization to access and/or drive a motor vehicle (1), in the manner of a keyless entry/go functionality. The locking system (3) comprises a first device (4), having at least two states and being configured as a control system, such as a control system for unlocking and/or locking the car doors (6), the ignition lock, the steering wheel lock, for releasing and/or blocking the immobilizer, the motor control device or the like, and an associated second device (5), in the form of an electronic key, an ID transmitter, a chip card or the like. Both devices (4, 5) have transmitters and/or receivers especially for electromagnetic signals (7) for their intended use. At least one of the signals (7) transmitted between the second device (5) and the first device (4) is a coded operating signal for authenticating said second device (5) so that once the transmitted operating signal has been positively identified for the authorized second device (5), the state of the first device (4) can be modified. The second device (5) and/or the first device (4) has a filter for reducing and/or suppressing interferences.