Cell Configuration for Rapid Switching in Unlicensed Bands
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing cell selection and switching methods in unlicensed frequency bands for mobile communication systems suffer from long delays and unreliable channel occupation due to competitive channel usage by various Radio Access Technologies, leading to deteriorated User Perspective Throughput and increased transmission delay.
Innovation Solution
A method and device for configuring cells in a mobile communication system that enables rapid cell switching by pre-configuring multiple cells in both licensed and unlicensed frequency bands, allowing a base station to monitor and select the best cell for a terminal in a short time unit, using Licensed-Assisted Access (LAA) and Carrier Aggregation (CA) technologies to manage channel occupation effectively.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If existing cell selection and switching methods are used in unlicensed frequency bands, then channel occupation is attempted, but long delays occur and channel occupation becomes unreliable due to competitive usage by various Radio Access Technologies
Solution Approach 1:
The base station pre-configures multiple candidate cells (second cells) in unlicensed bands and monitors their channel occupation states in advance. When the current cell becomes unavailable, the terminal can immediately switch to a pre-monitored candidate cell without waiting for channel sensing, thereby reducing switching delay and improving reliability
Solution Approach 2:
The base station acts as an intermediary that monitors channel occupation states of multiple candidate cells on behalf of the terminal. This intermediary monitoring allows the terminal to switch cells rapidly without performing its own lengthy channel sensing procedures, resolving the contradiction between fast switching and reliable channel occupation
2Speed
If multiple cells in unlicensed bands are configured and monitored, then quick cell switching is enabled, but device complexity increases
Solution Approach 1:
The cell configuration is segmented into a first cell (in licensed band) for initial connection and multiple second cells (in unlicensed bands) for rapid switching. This segmentation allows the complex monitoring task to be distributed, with the base station handling unlicensed band monitoring while the terminal focuses on licensed band communication and rapid switching execution
3Adaptability or versatility
If the number of configured second cells exceeds the number of cells that can support Carrier Aggregation, then more cell switching options are available, but device complexity and resource requirements increase
Solution Approach 1:
The base station pre-configures an extended set of candidate cells beyond what the terminal can handle through standard Carrier Aggregation. These additional cells are monitored by the base station in advance, allowing the terminal to access more switching options without proportionally increasing its own configuration complexity, as the base station performs the heavy lifting of monitoring and management
Data Source
AI summary
A method and a device for selecting a cell in a mobile communication system and for selecting a cell for transmitting data, by a base station, not only in a licensed frequency band but in an unlicensed frequency band. A method for configuring a cell of a base station includes connecting with a terminal through a first cell of a licensed band; transmitting, to the terminal, a message for configuring multiple second cells in an unlicensed band through the first cell; and monitoring the configured multiple second cells in the unlicensed band, wherein the number of the multiple second cells exceeds the number of cells, a carrier aggregation of which the terminal can support. The present disclosure relates to a 5G or a pre-5G communication system to be provided in order to support a higher data transmission rate after a 4G communication system such as an LTE.