Multi-Cell PDCCH Monitoring With HARQ-ACK Triggered Resumption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems face challenges in accurately and efficiently transmitting and receiving signals, particularly in managing physical downlink control channel (PDCCH) monitoring in multiple cells, leading to inefficiencies and potential delays in signal processing.
Innovation Solution
A method and apparatus for monitoring PDCCH in multiple cells, including PDCCH monitoring skipping based on downlink control information (DCI), reporting hybrid automatic repeat request-acknowledgment (HARQ-ACK) responses, and resuming PDCCH monitoring on a scheduling cell when a negative acknowledgment (NACK) is received, allowing for early termination of skipping and retransmission management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If PDCCH monitoring is continuously performed in multiple cells, then signal reception reliability is improved, but system complexity and processing overhead increase
Solution Approach 1:
The patent implements dynamic PDCCH monitoring by allowing the terminal to flexibly adjust monitoring behavior based on reception status. When PDSCH reception fails (NACK), the terminal dynamically resumes monitoring on the scheduling cell; when reception succeeds (ACK), monitoring can be skipped. This dynamic adaptation resolves the contradiction by maintaining reliability only when necessary while reducing complexity during normal operation.
Solution Approach 2:
The patent changes the monitoring parameter state based on HARQ-ACK feedback. The monitoring state transitions between active and skipped states depending on whether NACK or ACK is received. This parameter change mechanism allows the system to maintain high reliability during error conditions while reducing processing overhead during successful transmission, thus resolving the contradiction between reliability and complexity.
2Productivity
If PDCCH monitoring is skipped to reduce processing overhead, then system efficiency is improved, but signal reception reliability deteriorates
Solution Approach 1:
The patent employs HARQ-ACK feedback as the trigger mechanism for resuming PDCCH monitoring. When the terminal sends NACK feedback indicating failed PDSCH reception, it simultaneously triggers the resumption of monitoring on the scheduling cell. This feedback-based control ensures that monitoring is restored exactly when reliability is compromised, resolving the contradiction by maintaining efficiency during normal operation while ensuring reliability when needed.
Solution Approach 2:
The patent prepares the terminal to resume monitoring in advance by maintaining the capability to quickly react to NACK feedback. The terminal pre-configures monitoring parameters and can immediately resume monitoring when feedback indicates failure, rather than waiting for extended delays. This preliminary preparation resolves the contradiction by enabling rapid response to reliability issues while maintaining efficiency during successful operations.
3Productivity
If PDCCH monitoring is resumed upon NACK transmission, then retransmission efficiency is improved, but monitoring overhead increases
Solution Approach 1:
The patent segments the monitoring resumption action to apply only to the specific scheduling cell that experienced the failure, rather than resuming monitoring on all cells. This selective segmentation allows the terminal to improve retransmission efficiency for the affected cell while minimizing the time loss from monitoring overhead on other cells, thus resolving the contradiction between retransmission efficiency and monitoring overhead.
Solution Approach 2:
The patent applies monitoring resumption locally to only the scheduling cell where PDSCH reception failed, as identified by the NACK feedback. Other cells continue their normal monitoring or skipping patterns without interruption. This local quality approach ensures that retransmission efficiency is improved for the specific failed transmission while minimizing the overall monitoring overhead across the multi-cell system.
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
Disclosed herein is a method of monitoring a PDCCH by a terminal in a wireless communication system, the method including performing PDCCH monitoring in one or more scheduling cells configured for PDSCH scheduling among a plurality of cells, starting PDCCH monitoring skipping on a first scheduling cell based on first DCI detected through the PDCCH monitoring, performing reception related to at least one PDSCH in at least one of the plurality of cells, reporting a HARQ-ACK response for the at least one PDSCH, and resuming the PDCCH monitoring on the first scheduling cell. The PDCCH monitoring may be resumed on the first scheduling cell, based on that the HARQ-ACK response includes a NACK for a first PDSCH and that the first PDSCH has been scheduled through the first scheduling cell.