Mobile Device Indoor Positioning via Signal Propagation Time

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional motion sensors for indoor positioning of mobile devices are inaccurate due to limitations in step detection and orientation determination, especially in indoor environments where satellite signals are unreliable.

Innovation Solution

A method using signal propagation time parameters to determine point coordinates and motion information for mobile devices, allowing for accurate positioning and motion tracking without relying on conventional motion sensors, even when some installation positions of radio devices are unknown.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional motion sensors (accelerometer, gyroscope) are used for indoor positioning, then the positioning system can operate indoors without satellite signals, but the positioning accuracy deteriorates due to limitations in step detection and orientation determination

Engineering Contradiction:
Improveindoor positioning capabilityVSAvoidpositioning accuracy
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The patent replaces conventional mechanical motion sensors (accelerometers, gyroscopes) with a radio-based positioning system that uses signal propagation time measurements from multiple radio devices to determine position and motion information. This substitution eliminates the limitations of step detection and orientation determination inherent in mechanical sensors.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces signal propagation time parameters as an intermediary measurement quantity. By measuring the time for radio signals to travel between the mobile device and multiple radio devices, the system indirectly determines position and motion information with higher accuracy than direct mechanical sensing.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If signal propagation time parameters from multiple radio devices are used to determine position, then positioning accuracy improves, but system complexity increases due to the need for multiple installation positions and coordinate system calculations

Engineering Contradiction:
Improvepositioning accuracyVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent makes the mobile device itself perform multiple functions: it serves as both the positioning target and the calculation unit. The mobile device determines its own position and motion information by processing signal propagation time parameters from multiple radio devices, eliminating the need for a separate centralized positioning server and reducing overall system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The mobile device performs self-positioning and self-motion-tracking by autonomously calculating its position coordinates and motion information based on received signal propagation time parameters. This self-service approach reduces dependency on complex external infrastructure.

Inventive Principle:
Principle #25Self-service

3Ease of manufacture

If conventional motion sensors are used, then the system implementation is simple, but the motion information accuracy deteriorates due to error accumulation in step detection and orientation determination

Engineering Contradiction:
Improvesystem implementation simplicityVSAvoidmotion information accuracy
Core Design Contradiction:
Ease of manufactureVSMeasurement precision

Solution Approach 1:

The patent replaces mechanical motion sensors with a radio-based measurement system that determines motion information through signal propagation time calculations. This substitution eliminates error accumulation in step detection and orientation determination while maintaining relatively simple system implementation through the use of existing radio communication infrastructure.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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

This approach provides accurate and flexible indoor positioning and motion tracking by determining motion information based on signal propagation times, reducing errors associated with conventional sensor shortcomings and enabling seamless navigation indoors.

Implementation Method 1

obtaining or determining a plurality of signal propagation time parameters, wherein each of the plurality of signal propagation time parameters is representative of a respective signal propagation time value of one or more radio signals traveling between the respective observation position and the respective installation position

Methodology Applied
Scientific EffectSignal propagation time measurement: Time of Flight

Data Source

PatentEP3690470B1Determining motion information associated with a mobile device
Publication Date: 2022.12.07 HERE GLOBAL BV
  • EP3690470B1 patent drawingFigure 1
  • EP3690470B1 patent drawingFigure 2~4
  • EP3690470B1 patent drawingFigure 5

AI summary

It is inter-alia disclosed a method comprising: obtaining or determining a plurality of signal propagation time parameters, wherein each of said plurality of signal propagation time parameters is associated with a respective observation position of a plurality of observation positions (102-1, 102-2, 102-3) of a mobile device (400) and a respective installation position of a plurality of installation positions of a plurality of radio devices (300-1, 300-2, 300-3), determining, for each of said plurality of installation positions of said plurality of radio devices, respective point coordinates of said respective radio device, at least partially based on said plurality of signal propagation time parameters, and determining motion information associated with said mobile device at least partially based on said plurality of signal propagation time parameters and said point coordinates.