DSS Uplink Subcarrier Shift Access Barring for LTE Interference

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Solution Overview

Problem

Existing NR UEs not configured with uplink shift cause interference when sharing spectrum with LTE UEs, leading to decoding errors and loss of connection, as they lack the necessary uplink subcarrier alignment.

Innovation Solution

Implement signaling enhancements using cell-barring with additional filters to differentiate between NR UEs with and without uplink shift, allowing only compatible UEs to access the cell by broadcasting specific information elements and additional fields in system information blocks.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If NR UEs without uplink shift configuration are allowed to access the cell, then device accessibility is improved, but interference with LTE UEs increases causing decoding errors and connection loss

Engineering Contradiction:

Improvedevice accessibilityVSAvoidinterference

Core Design Contradiction:

Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The network performs preliminary action by broadcasting system information blocks before UE access that contain filtering criteria and barring information. This allows UEs to self-determine eligibility before attempting access, preventing interference-prone UEs from accessing the cell in the first place rather than addressing interference after it occurs.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent introduces an intermediary mechanism - the system information block with filtering criteria - that mediates between the network's desire to allow all NR UEs access and the need to prevent interference. This intermediary structure enables selective access control without requiring direct UE-network negotiation for each access attempt.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Object-affected harmful factors

If cell-barring with additional filters is implemented to prevent interference, then interference prevention is improved, but system complexity increases

Engineering Contradiction:

Improveinterference preventionVSAvoidsystem complexity

Core Design Contradiction:

Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The system information block serves multiple functions simultaneously: it broadcasts cell status, carries filtering criteria for UE selection, provides barring information, and enables UE self-determination of eligibility. This multi-functionality reduces the need for separate signaling mechanisms and complex access control procedures.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The patent implements self-service by enabling UEs to autonomously determine their eligibility for cell access by reading and processing the system information blocks. Each UE independently evaluates its own capabilities against the broadcast criteria without requiring network intervention or complex centralized management.

Inventive Principle:

Principle #25Self-service

Data Source

PatentUS12490110B2Methods, systems, and apparatuses for handling dynamic spectrum sharing with uplink subcarrier shift

Publication Date: 2025.12.02 APPLE INC

AI summary

Embodiments described herein include methods, systems, and apparatuses for allowing a user equipment (UE) that supports dynamic spectrum sharing (DSS) with uplink (UL)-shift to access a cell and barring UEs that do not support DSS with UL-shift. Embodiments may use a cell barring field in a master information block and additional filters to indicate a barring state for a network node.