AP Obstacle Recognition via Terminal Path Loss Inference

Solution Overview

Problem

In wireless local area networks, obstacles such as beams, pipes, or walls between access point (AP) devices lead to inaccurate received signal strength indication (RSSI) measurements, affecting radio calibration results.

Innovation Solution

An obstacle recognition method that compares actual path loss values between APs with inferred path loss values based on path loss value pairs between terminals and AP pairs, to determine if an obstacle exists between APs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If radio calibration is performed using RSSI measurements between AP devices, then channel throughput can be improved by reducing signal interference, but measurement precision deteriorates when obstacles exist between AP devices

Engineering Contradiction:

Improvechannel throughputVSAvoidRSSI measurement accuracy

Core Design Contradiction:

ProductivityVSMeasurement precision

Solution Approach 1:

The patent introduces terminal devices as intermediary measurement points between AP devices. Instead of directly measuring RSSI between APs (which may be blocked by obstacles), the system uses terminals to measure and report path loss values to a network device, which then infers AP-to-AP path loss through calculation. This intermediary approach bypasses physical obstacles and improves measurement accuracy.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces direct physical signal measurement between APs with a computational inference system. The network device collects path loss values from multiple terminal measurements and uses algorithms to infer the AP-to-AP path loss, substituting mechanical/direct measurement with information processing and calculation to overcome physical obstructions.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

2Ease of operation

If direct RSSI measurement is used between AP devices, then the measurement process is simple, but measurement precision deteriorates due to obstacles blocking the signal path

Engineering Contradiction:

Improvemeasurement simplicityVSAvoidRSSI measurement accuracy

Core Design Contradiction:

Ease of operationVSMeasurement precision

Solution Approach 1:

The patent introduces terminal devices as intermediary measurement points between AP devices. Instead of directly measuring RSSI between APs (which may be blocked by obstacles), the system uses terminals to measure and report path loss values to a network device, which then infers AP-to-AP path loss through calculation. This intermediary approach bypasses physical obstacles and improves measurement accuracy.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent replaces direct physical signal measurement between APs with a computational inference system. The network device collects path loss values from multiple terminal measurements and uses algorithms to infer the AP-to-AP path loss, substituting mechanical/direct measurement with information processing and calculation to overcome physical obstructions.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

3Measurement precision

If path loss values are inferred from multiple AP pairs, then measurement precision improves by avoiding obstacles, but device complexity increases due to additional measurement requirements

Engineering Contradiction:

Improvepath loss inference accuracyVSAvoidsystem complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent makes terminal devices perform multiple functions: they serve as both wireless clients connecting to APs and as measurement instruments for path loss detection. The same terminal infrastructure used for normal network access is leveraged for calibration measurements, eliminating the need for dedicated measurement equipment and reducing overall system complexity.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system uses existing network resources (terminals and their normal communication infrastructure) to perform the measurement function. Terminals that are already part of the network selflessly provide measurement data during their normal operation, and the network device automatically processes this data for calibration purposes without requiring separate dedicated measurement systems.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS12273152B2Obstacle recognition method and related device

Publication Date: 2025.04.08 HUAWEI TECH CO LTD

AI summary

An obstacle recognition method and apparatus, and a related device are provided. The method includes: obtaining an actual path loss value between a first AP and a second AP, path loss value pairs between a terminal and a plurality of AP pairs, and path loss values of the plurality of AP pairs; obtaining, based on the path loss value pairs between the terminal and the plurality of AP pairs, an AP pair similar to an AP pair formed by the first AP and the second AP; obtaining a second path loss value between the first AP and the second AP based on a path loss value of the similar AP pair; and comparing the second path loss value between the first AP and the second AP with the actual path loss value, to determine whether an obstacle exists between the first AP and the second AP.