Cell Reselection Offset and Hysteresis for Wireless Access Points

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Solution Overview

Problem

Wireless communication systems face challenges in efficiently reselecting access points to ensure continuous and optimal service as mobile devices move, particularly in balancing signal quality, data throughput, and billing preferences, with existing methods lacking in effectively favoring preferred access points for extended coverage and service retention.

Innovation Solution

Mobile devices apply an offset to measurement parameters of preferred access points during cell reselection, and utilize hysteresis values when connected to these points, to enhance their desirability and maintain connectivity for longer durations, thereby favoring preferred access points over others.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Duration of action of moving object

If offsets are applied to favor preferred access points during cell reselection, then service retention and connectivity duration are improved, but coverage range is reduced

Engineering Contradiction:
Improveconnectivity durationVSAvoidcoverage area
Core Design Contradiction:
Duration of action of moving objectVSArea of stationary object

Solution Approach 1:

The patent applies offset values to measurement parameters of preferred access points, modifying the ranking criteria to favor these points. This parameter change allows the mobile device to maintain connectivity with preferred access points for extended durations even when signal quality would normally warrant reselection to other access points.

Inventive Principle:
Principle #35Parameter changes

2Stability of the object's composition

If hysteresis values are applied to preferred access points, then service consistency is improved, but reselection flexibility is reduced

Engineering Contradiction:
Improveservice consistencyVSAvoidreselection flexibility
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The patent applies hysteresis values as a preliminary anti-action to prevent frequent reselection between preferred and non-preferred access points. By adding this stabilizing factor before reselection decisions are made, the system reduces measurement fluctuations and maintains service consistency with preferred access points.

Inventive Principle:
Principle #9Preliminary anti-action

3Adaptability or versatility

If offsets are applied to expand coverage of preferred access points, then service availability is improved, but measurement accuracy is reduced

Engineering Contradiction:
Improveservice availabilityVSAvoidmeasurement accuracy
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The patent introduces offset values as intermediary adjustments to measurement parameters. These offsets act as mediators that expand the effective coverage area of preferred access points by modifying measurement rankings, thereby improving service availability while managing the trade-off with measurement precision.

Inventive Principle:
Principle #24Intermediary (Mediator)

Data Source

PatentEP2220896B1Favoring access points in wireless communications
Publication Date: 2018.01.24 QUALCOMM INC
  • EP2220896B1 patent drawingFigure 1
  • EP2220896B1 patent drawingFigure 2
  • EP2220896B1 patent drawingFigure 3

AI summary

Systems and methodologies are described that facilitate applying offsets and/or selectable hysteresis values to favor access points in cell reselection. In measuring and ranking surrounding access points in reselection, offsets can be applied to favorable access points to facilitate cell reselection thereto. The offset can positively affect measurements, and thus ranking as well, in some cases. Negative offsets can also be applied to lower measurements (and thus ranking) of some access points. Moreover, hysteresis values can be applied in measuring current cells to prevent frequent reselection. The hysteresis values can be selected based on a type of the current cell or related access point to expand the coverage area where desired. Thus, where the current access point is favorable, a larger hysteresis can be added to measurements related to the current access point.