UE Carrier Aggregation Capability Reporting Segmentation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Legacy carrier aggregation (CA) signaling in wireless telephony becomes excessively burdensome as the number of supported carriers increases, leading to increased system overhead due to the need to report detailed capabilities for each band combination, including fallback configurations, which may exceed the current PDCP PDU size limit.

Innovation Solution

The proposed solution involves reporting UE Radio Frequency (RF) and Baseband (BB) capabilities separately and disassociating them from CA band configurations, allowing implicit fallback capability signaling, thereby reducing the need to transmit full capability sets for each supported band combination.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Loss of information

If legacy CA signaling reports detailed capabilities for each band combination including fallback configurations, then the network becomes aware of complete UE capabilities, but the signaling data volume becomes excessively large and may exceed PDCP PDU size limit

Engineering Contradiction:
ImproveCA capability information completenessVSAvoidsignaling data volume
Core Design Contradiction:
Loss of informationVSQuantity of substance

Solution Approach 1:

The UE capability reporting is segmented into two independent parts: RF capabilities (frequency bands, band combinations, carrier bandwidths, multiple TimingAdvance support, simultaneous Tx/Rx support) and baseband processing capabilities (number of MIMO layers, number of CSI processes, NAIC capability). This segmentation allows each part to be reported separately, reducing the total signaling overhead while maintaining complete capability information.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The patent extracts and removes the redundant fallback capability reporting from the traditional band combination-specific reporting. Instead of reporting full capabilities for each possible fallback scenario, the UE reports its maximum RF and baseband capabilities once, and the network infers fallback capabilities from these maximum capabilities, significantly reducing signaling data volume.

Inventive Principle:
Principle #2Taking out (Extraction)

2Productivity

If the number of aggregated carriers is increased to support more bandwidth, then the network capacity and user data rates increase, but the CA capability signaling burden increases significantly

Engineering Contradiction:
Improvenetwork capacity and user data ratesVSAvoidCA capability signaling complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent creates universal RF and baseband capability parameters that apply across all band combinations. The UE reports its maximum supported RF capabilities (frequency bands, bandwidths, simultaneous Tx/Rx) and baseband processing capabilities (MIMO layers, CSI processes) as universal parameters that can be applied to any carrier aggregation configuration, eliminating the need for separate capability reporting for each band combination.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

Instead of reporting the minimum necessary capabilities for each specific band combination, the patent applies partial action by reporting the maximum RF and baseband capabilities once. The network then uses these maximum capabilities to determine appropriate configurations for any number of aggregated carriers, avoiding the excessive action of reporting all possible fallback scenarios.

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP3326318B1Separate reporting of RF and BB capabilities of a mobile user equipment in a wireless communications system supporting carrier aggregation
Publication Date: 2020.09.02 TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
  • EP3326318B1 patent drawingFigure 1~2
  • EP3326318B1 patent drawingFigure 3~4
  • EP3326318B1 patent drawingFigure 5~6

AI summary

An inventive UE carrier aggregation (CA) capability reporting signalling model allows UEs (30) aggregating large numbers of component carriers to transmit CA-relevant capabilities to the network more efficiently than the current (legacy) signalling model. Rather than reporting CA/MIMO/CSI/NAICS capabilities separately for each supported band combination, including fallback configurations, embodiments of the present invention either report UE Radio Frequency (RF) and Baseband (BB) related capabilities separately, or report them disassociated from CA band configurations. This approach avoids the need to signal the full UE (30) set of capabilities for each of (possibly many) supported band combinations. Furthermore, fallback capabilities are signalled implicitly, eliminating the need to transmit this data.