UE Capability Signaling for LTE-NR Tight-Interworking

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The complexity of user equipment (UE) capability signaling in LTE networks is increased by the introduction of New Radio (NR) capabilities, complicating the signaling structure and requiring new solutions to maintain minimal impact on LTE specifications during 5G tight-interworking scenarios.

Innovation Solution

Incorporating LTE+NR capability information into a transparent container within LTE capability signaling messaging, allowing the NR node to select configurations and inform the LTE node of usable capabilities, thereby minimizing changes to LTE specifications and coordinating band combinations and Layer 2 buffer capabilities across different radio access technologies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If NR capabilities are added to LTE capability structure, then joint capability information for LTE-NR interworking is provided, but the complexity of LTE capability signaling increases

Engineering Contradiction:

Improvejoint capability informationVSAvoidcapability signaling complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The capability information is segmented into separate LTE capability information and NR capability information, transmitted in distinct messages. The LTE node processes only LTE capabilities while the NR node processes NR capabilities, avoiding the need to handle combined joint capability information and reducing signaling complexity at each node.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The NR capability information is extracted from the joint capability structure and transmitted separately to the NR node. This extraction allows the LTE node to ignore NR capabilities and only process LTE-related information, thereby reducing the complexity burden on LTE nodes while still providing necessary joint capability information to the appropriate node.

Inventive Principle:

Principle #2Taking out (Extraction)

2Ease of operation

If joint capability information is provided to LTE node, then LTE node can configure interworking, but LTE node must understand and process NR capability information

Engineering Contradiction:

Improveinterworking configurationVSAvoidcapability information processing

Core Design Contradiction:

Ease of operationVSDifficulty of detecting and measuring

Solution Approach 1:

The NR node acts as an intermediary that receives joint capability information containing both LTE and NR capabilities. It extracts and processes the NR capability portion, then provides only the necessary LTE capability information to the LTE node. This intermediary role shields the LTE node from the complexity of understanding NR capabilities while still enabling proper interworking configuration.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The capability information processing is segmented such that the NR node handles NR capability extraction and the LTE node handles only LTE capability configuration. This segmentation allows each node to operate within its expertise domain without needing to understand the other RAT's capability structure, simplifying the processing difficulty for each node.

Inventive Principle:

Principle #1Segmentation

3Device complexity

If independent capability information for NR and LTE is used, then each node processes only its own RAT capabilities, but coordination of band combinations and buffer capabilities across RATs becomes difficult

Engineering Contradiction:

Improvenode processing complexityVSAvoidcross-RAT coordination

Core Design Contradiction:

Device complexityVSAdaptability or versatility

Solution Approach 1:

The NR node is given multi-functionality to handle both NR capability processing and LTE-NR coordination tasks. It receives joint capability information, processes both LTE and NR capabilities, coordinates band combinations and buffer capabilities across RATs, and then distributes appropriate information to each node. This universal handling at the NR node enables cross-RAT coordination while keeping individual node processing simple.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system implements feedback mechanisms where the NR node receives joint capability information, processes it, and provides feedback to the LTE node about which LTE capabilities are available for interworking configuration. This feedback loop enables coordinated decision-making across RATs while maintaining independent processing at each node, resolving the contradiction between simplicity and coordination.

Inventive Principle:

Principle #23Feedback

Data Source

PatentUS11729848B2UE capability signaling for tight-interworking

Publication Date: 2023.08.15 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)

AI summary

This disclosure provides mechanisms for User Equipment, UE, capability signaling and coordination for Long Term Evolution (LTE) and New Radio (NR) tight-interworking without increasing the complexity of LTE capability reporting. This disclosure proposes a capability signaling and coordination framework in order to coordinate at least band combinations and Layer 2 buffer capabilities across the master and the secondary nodes which are of different Radio Access Technologies (RATs), such as LTE and NR.