Mobile Device Indoor Positioning via Motion Correlation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining the location of a mobile device within a building are either imprecise, computation-intensive, or invasive to user privacy, as they require external servers or extensive device capabilities.
Innovation Solution
A method utilizing an inertial motion sensor in the mobile device and an optical motion detector in room devices to correlate movement data, with the room device sending a radio message containing its position and signal strength, allowing the mobile device to determine its location without external servers or identity disclosure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If terminal-based radio positioning is used, then location determination is achieved, but computation intensity increases significantly
Solution Approach 1:
The patent extracts the computation-intensive positioning task from the mobile device and transfers it to stationary room devices. The mobile device only needs to measure signal strengths and correlate them with motion data, while the room devices perform the actual position computation based on pre-stored field strength maps, significantly reducing mobile device computation intensity.
Solution Approach 2:
The system performs preliminary actions by pre-measuring and storing field strength maps in the room devices before actual positioning is needed. This allows the mobile device to determine location through simple comparison of current measurements with pre-stored data, avoiding real-time computation intensity while maintaining accuracy.
2Measurement precision
If server-based radio positioning is used, then positioning computation is performed centrally, but user privacy is compromised
Solution Approach 1:
The patent segments the centralized server-based positioning system into distributed room devices located within the building. Each room device independently stores and processes field strength maps for its local area, eliminating the need for a central server that would collect and process user location data, thus preserving user privacy while maintaining positioning accuracy.
Solution Approach 2:
The room devices perform self-service by autonomously storing and using their own field strength maps to determine mobile device positions. This eliminates dependency on external servers that would require user identity disclosure, allowing positioning to occur locally without compromising user privacy.
3Measurement precision
If local beacons with reading units are installed, then room identification is achieved, but additional device infrastructure is required
Solution Approach 1:
The patent makes room devices multi-functional by equipping them with both motion detection capabilities and field strength map storage. This allows a single device type to perform both occupancy detection and positioning functions, eliminating the need for separate beacon infrastructure and reducing overall system complexity while maintaining room identification accuracy.
Solution Approach 2:
The patent merges the functions of motion detectors and positioning beacons into a single integrated room device. By combining these previously separate infrastructure elements, the system reduces device complexity and infrastructure requirements while achieving both occupancy detection and accurate room identification.
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 method provides precise room-level location determination while protecting user identity and privacy, using existing mobile and room device technologies, and is cost-effective without the need for additional infrastructure.
Implementation Method 1
an optical motion detector of a room device installed in a room to identify a movement in the room
Implementation Method 2
uses an inertial motion sensor of a mobile device and an optical motion detector of a room device
Implementation Method 3
the respective room device sends a radio message containing its own position and the respective mobile device receives this radio message
Implementation Method 4
the respective mobile device receives this radio message and in so doing measures the signal strength thereof
Data Source
AI summary
When an optical motion detector of a room device detects movement in a room in which it is installed, the room device transmits a radio message including its position. Upon receiving the radio message, a mobile device measures the signal strength to determine whether it is high. If the movement detected by the optical motion detector correlates chronologically with movement detected by an inertial movement sensor of the mobile device, the mobile device concludes that the mobile device is located in the room or in proximity of the position of the room device. The identity of the mobile device is protected, as no server or other device is required for positioning to which the mobile device would have to disclose the identity, position or sensor information thereof.