Pedestrian Localization Using Hierarchical Memory Tier Pre-fetching

Solution Overview

Problem

Existing mobile device indoor navigation systems face challenges in achieving seamless and accurate localization within enclosed spaces due to limited memory and processing resources, leading to high processing latency and reduced responsiveness.

Innovation Solution

The implementation of a system that pre-fetches fingerprint-mapped data using hierarchically-assigned memory resource portions, allowing for faster localization of mobile devices along pedestrian routes by dynamically replacing data as the user moves, thereby optimizing memory usage and processing efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If comprehensive fingerprint data of entire facility is stored in mobile device memory, then localization accuracy is improved, but memory resource consumption increases and processing latency increases

Engineering Contradiction:

Improvelocalization accuracyVSAvoidmemory resource consumption

Core Design Contradiction:

Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent divides the comprehensive fingerprint data into hierarchical segments: a first portion of fingerprint data is stored in a first memory tier, and a second portion is stored in a second memory tier. This segmentation allows the system to balance between having sufficient data for accurate localization and managing limited mobile device memory resources effectively.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The system performs preliminary actions by pre-fetching the second portion of fingerprint data from the second memory tier to the first memory tier before it is actually needed for localization. This anticipatory data loading reduces processing latency when localization is required, while still maintaining efficient use of memory resources by not permanently storing all data in the faster first tier.

Inventive Principle:

Principle #10Preliminary action

2Measurement precision

If comprehensive fingerprint data of entire facility is stored in mobile device memory, then localization accuracy is improved, but processing latency increases

Engineering Contradiction:

Improvelocalization accuracyVSAvoidprocessing latency

Core Design Contradiction:

Measurement precisionVSLoss of time

Solution Approach 1:

The system performs preliminary actions by pre-fetching the second portion of fingerprint data from the second memory tier to the first memory tier before it is actually needed for localization. This anticipatory data loading reduces processing latency when localization is required, while still maintaining efficient use of memory resources by not permanently storing all data in the faster first tier.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system dynamically manages fingerprint data between two memory tiers based on current localization needs and predicted user movement. The localization logic module dynamically determines when to pre-fetch data and which data to pre-fetch, adapting to changing conditions rather than using a static memory allocation strategy.

Inventive Principle:

Principle #15Dynamics

3Productivity

If fingerprint data is pre-fetched into first memory tier, then localization responsiveness is improved, but memory resource constraints worsen

Engineering Contradiction:

Improvelocalization responsivenessVSAvoidmemory resource constraints

Core Design Contradiction:

ProductivityVSQuantity of substance

Solution Approach 1:

Instead of loading all fingerprint data into the first memory tier, the system performs partial action by loading only the necessary second portion of fingerprint data that is likely to be needed soon, based on predicted user movement along the pedestrian route. This partial pre-fetching improves responsiveness without excessively consuming memory resources.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The system performs preliminary actions by pre-fetching the second portion of fingerprint data from the second memory tier to the first memory tier before it is actually needed for localization. This anticipatory data loading reduces processing latency when localization is required, while still maintaining efficient use of memory resources by not permanently storing all data in the faster first tier.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentEP3534111B1Method and system of pedestrian localization

Publication Date: 2020.12.30 MAPSTED CORP

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AI summary

Systems and methods for localizing a mobile device along a pedestrian route traversed in an indoor area are described. For example, the mobile device may be localized to an estimated first position within the indoor area based on accessing, from a first memory tier of the memory, a first portion fingerprint data that includes fingerprint data of a first subset area of the indoor area, the first subset area at least partly surrounding the estimated first position Further, a traversal of the device may be detected along the route to an estimated second position. When a difference between the estimated first and second positions exceeds a threshold distance, the first portion fingerprint data of first memory tier is replaced upon pre-fetching a second portion fingerprint data including fingerprint data of a second subset area of the indoor area, the second subset area at least partly surrounding the estimated second position.