Uplink Control Channel Configuration for Carrier Aggregation Overhead
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In LTE systems with carrier aggregation, the existing mechanisms do not support simultaneous sending of uplink control information, such as Scheduling Request (SR), Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK), and Channel State Information (CSI), on both the primary serving cell (PCell) and secondary serving cell (SCell), leading to overhead issues on the PCell, especially in scenarios with a large number of small cells.
Innovation Solution
A method and apparatus that configure and send the uplink control channel by allowing PUCCH to be sent on both the PCell and SCell, with the base station sending messages to the user equipment to determine the appropriate serving cells using predefined rules, such as index, frequency, or bandwidth criteria, to distribute the control information across multiple cells.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If PUCCH is limited to be sent only on PCell, then the existing carrier aggregation mechanism is simple, but the overhead of PUCCH on PCell becomes a problem when the number of small cells is huge
Solution Approach 1:
The patent segments the PUCCH transmission function by introducing a second sending mode where PUCCH can be transmitted on both PCell and SCell. This divides the control channel overhead across multiple cells, reducing the burden on PCell while maintaining system functionality.
2Quantity of substance
If PUCCH is sent on both PCell and SCell, then the PUCCH overhead on PCell is reduced, but corresponding mechanisms are required to ensure normal operation of terminals
Solution Approach 1:
The patent implements dynamic switching between first sending mode (PUCCH only on PCell) and second sending mode (PUCCH on both PCell and SCell). The base station can flexibly configure the sending mode based on system conditions, allowing the system to adapt to different scenarios and balance overhead reduction with operational simplicity.
3Ease of operation
If PUCCH is sent only on PCell, then terminal operation is simple, but system capacity is limited when serving many small cells
Solution Approach 1:
The patent extends the PUCCH transmission dimension from a single cell (PCell only) to multiple cells (PCell and SCell). This dimensional expansion allows the system to serve more small cells effectively by distributing control information across multiple transmission paths, thereby increasing system capacity while maintaining operational simplicity through configurable modes.
Data Source
AI summary
A method and apparatus for configuring and sending an uplink control channel, a base station, and a User Equipment (UE) are described. The method includes sending, by a base station, a message to a user equipment. The message is used for configuring a sending mode for a physical uplink control channel (PUCCH) of the user equipment. The sending mode includes a first sending mode in which the PUCCH is sent only on an uplink primary serving cell, and a second sending mode in which the PUCCH is sent on the uplink primary serving cell and an uplink secondary serving cell.