Wireless Environment Estimation Using Inflector Locus Constraints

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current wireless communication systems face challenges in accurately detecting, tracking, and characterizing objects in their environment due to channel distortions and multipath effects, which affect signal quality and positioning accuracy.

Innovation Solution

The method involves processing system state information and received waveform data to estimate the location of inflectors in the environment by using constraints based on path length differences and frequency offsets, combining these to determine the location of inflectors along an elliptical locus defined by the transmitter and receiver positions, even when these devices are non-stationary.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If channel estimation is performed using received signals distorted by multipath effects, then the channel estimate can be generated, but the positioning accuracy deteriorates due to inability to distinguish direct path from reflected signals

Engineering Contradiction:
Improvepositioning accuracyVSAvoidsignal quality
Core Design Contradiction:
Measurement precisionVSLoss of information

Solution Approach 1:

The patent segments the received signal into direct path components and multipath components by analyzing arrival times and applying constraints. The channel estimate is divided into direct path channel estimate and multipath channel estimate, allowing separate processing and positioning calculation that excludes multipath interference.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent introduces an intermediary constraint-based processing step that acts as a mediator between the raw received signal and the final channel estimate. This intermediary process identifies and separates multipath components before they corrupt the positioning calculation.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If environmental inflectors are detected using signal reflections, then object detection capability is improved, but false alerts increase due to difficulty in distinguishing real objects from environmental reflections

Engineering Contradiction:
Improveobject detection reliabilityVSAvoidfalse alerts
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent applies dynamics by tracking the movement of detected inflectors over time and comparing against predicted positions based on transmitter and receiver motion. Real objects exhibit different motion patterns than environmental reflections, allowing discrimination through temporal analysis.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent uses feedback by continuously updating the environment model with new detections and using this model to predict future inflector positions. Detected inflectors are cross-checked against predictions, and inconsistencies trigger further verification before generating alerts.

Inventive Principle:
Principle #23Feedback

3Measurement precision

If the system accounts for moving transmitters and receivers, then positioning accuracy in dynamic environments is improved, but the complexity of constraint calculations increases

Engineering Contradiction:
Improvepositioning accuracy in dynamic environmentsVSAvoidconstraint calculation complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent changes parameters by transforming the problem into a moving reference frame where the transmitter is stationary and the receiver moves. This parameter transformation simplifies the constraint equations while maintaining accuracy for dynamic positioning.

Inventive Principle:
Principle #35Parameter changes

4Measurement precision

If multipath components are removed from channel estimation, then positioning precision is improved, but the quantity of usable signal information decreases

Engineering Contradiction:
Improvepositioning precisionVSAvoidusable signal information
Core Design Contradiction:
Measurement precisionVSQuantity of substance

Solution Approach 1:

The patent applies partial action by selectively removing only the harmful multipath components from the channel estimate while retaining and utilizing the direct path signal information. This partial removal achieves positioning precision without excessive loss of usable signal information.

Inventive Principle:
Principle #16Partial or excessive 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

This approach enhances the accuracy of object detection and tracking in wireless communication systems, improving signal processing and positioning by accounting for moving objects and environmental reflections, thereby reducing false alerts and enhancing positioning precision.

Implementation Method 1

the inflector being an element in the environment causing reflection or diffraction of transmitted signals

Methodology Applied
Scientific EffectReflection: Reflection

Implementation Method 2

the inflector being an element in the environment causing reflection or diffraction of transmitted signals

Methodology Applied
Scientific EffectDiffraction: Diffraction

Implementation Method 3

the input signal being a combination of a direct path signal and a signal that propagates from the transmitter to the inflector and from the inflector to the receiver having a path length difference

Methodology Applied
Scientific EffectInterference: Interference

Implementation Method 4

Channel distortions may include amplitude distortions, frequency offsets, phase offsets, Doppler effects

Methodology Applied
Scientific EffectDoppler effect: Doppler Effect

Data Source

PatentEP2443473B1Environment estimation in a wireless communication system
Publication Date: 2023.04.12 COHDA WIRELESS
  • EP2443473B1 patent drawingFigure 1~2
  • EP2443473B1 patent drawingFigure 3~4
  • EP2443473B1 patent drawingFigure 5~6

AI summary

A method and system are described for estimating an environment surrounding a wireless communication system, the environment including at least one inflector that inflects transmitted signals. An observation generator (300) receives an input signal transmitted from a transmitter to a receiver via a wireless communication channel and also receives system state information pertaining to at least one of the receiver, the transmitter and the inflector. An observation processor (302) uses observations (303) from the observation generator (300) to estimate at least one property of the inflector based on the received input signal and the system state information.