Carrier Aggregation Control Channel Signaling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

In LTE-Advanced wireless communication systems, there is a challenge in efficiently conveying carrier aggregation information from base stations to wireless transmit/receive units (WTRUs) due to the need for backward compatibility with LTE Release 8 and the complexity of managing asymmetric and non-contiguous carrier configurations, which affects control channel signaling and acquisition.

Innovation Solution

The method involves using a broadcast channel to convey LTE-A specific control information, defining new master information blocks (MIBs) and system information blocks (SIBs) that are compatible with LTE-A WTRUs, and employing techniques like blind detection of the downlink control channel, discontinuous reception (DRX) operations, and signaling methods to reduce overhead and improve power efficiency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If carrier aggregation information is conveyed using traditional LTE control channels, then backward compatibility with LTE Release 8 is maintained, but the complexity of managing asymmetric and non-contiguous carrier configurations increases

Engineering Contradiction:
Improvebackward compatibilityVSAvoidcontrol channel signaling complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent segments carrier aggregation information into multiple parts: anchor carrier information is conveyed through traditional LTE control channels (maintaining backward compatibility), while additional component carrier information is conveyed through separate indication mechanisms. This segmentation allows the system to maintain compatibility with LTE Release 8 while supporting complex asymmetric and non-contiguous carrier configurations without overwhelming control channel overhead.

Inventive Principle:
Principle #1Segmentation

2Productivity

If multiple component carriers are aggregated to increase bandwidth, then data transmission rates improve, but the number of blind detections required increases

Engineering Contradiction:
Improvedata transmission rateVSAvoidblind detection time
Core Design Contradiction:
ProductivityVSLoss of time

Solution Approach 1:

The patent applies preliminary action by providing WTRUs with advance information about anchor carriers and component carrier configurations through broadcast channels and system information blocks before data transmission begins. This pre-signaling approach allows WTRUs to prepare their reception parameters in advance, significantly reducing the number of blind detections required when actual data transmission occurs on aggregated carriers, thereby maintaining high data rates while minimizing detection time overhead.

Inventive Principle:
Principle #10Preliminary action

3Reliability

If continuous monitoring of all component carriers is performed, then control information is reliably received, but power consumption increases

Engineering Contradiction:
Improvecontrol information receptionVSAvoidWTRU power consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent implements periodic action through discontinuous reception (DRX) mechanisms where WTRUs monitor component carriers periodically rather than continuously. The network configures DRX cycles and wake-up patterns that align with the periodic transmission of control information on aggregated carriers. This allows WTRUs to maintain reliable control information reception by monitoring only during scheduled intervals, significantly reducing power consumption compared to continuous monitoring while ensuring control information is not missed.

Inventive Principle:
Principle #19Periodic action

Data Source

PatentEP3113564B1Carrier aggregation
Publication Date: 2019.06.12 INTERDIGITAL PATENT HOLDINGS INC
  • EP3113564B1 patent drawingFigure 1
  • EP3113564B1 patent drawingFigure 2
  • EP3113564B1 patent drawingFigure 3

AI summary

A method and apparatus for handling a control channel for carrier aggregation in wireless communications. The method includes determining which component carrier to listen to, detecting the downlink control channel, processing mapping information related to downlink and uplink.