MAC CE Beam Failure Recovery Request Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In high-frequency band communications systems, beam failure recovery (BFR) mechanisms face challenges due to signal blocking, and existing technologies lack efficient methods for transmitting Beam Failure Recovery Request (BFRQ) information, particularly in Secondary Cell (SCell) BFR processes, where the data to transmit and the resource for transmission are not clearly resolved.
Innovation Solution
The method involves triggering the generation of a MAC Control Element (CE) for BFRQ by user equipment (UE), determining the latest available uplink resource, and sending the MAC CE using this resource, which can be configured, indicated by a grant, or obtained through a random access procedure, with priority determined based on preset relationships to ensure timely and reliable transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If radio link reconstruction is used for beam failure recovery, then the system can recover from beam failure, but the recovery time is too long
Solution Approach 1:
The patent applies preliminary action by pre-configuring multiple uplink resources (configured grant resources, random access resources, and dynamic grant resources) before beam failure occurs. When beam failure is detected, the UE can immediately use the pre-configured configured grant resource to send the BFRQ MAC CE without waiting for scheduling, thereby reducing recovery time while ensuring reliable recovery capability
2Reliability
If dedicated uplink resources are allocated for BFRQ transmission, then transmission reliability is improved, but resource allocation complexity increases
Solution Approach 1:
The patent applies universality by designing a multi-functional resource allocation mechanism where configured grant resources can serve both regular uplink transmission and BFRQ transmission. The same resource pool is used for different purposes depending on the situation, reducing the need for separate dedicated resources while maintaining transmission reliability through prioritized access
3Productivity
If the UE waits for scheduled uplink resources to send BFRQ, then resource utilization is optimized, but transmission timeliness deteriorates
Solution Approach 1:
The patent applies dynamics by creating a dynamic resource selection mechanism where the UE can switch between different uplink resource types based on real-time conditions. The configured grant resource provides immediate transmission capability when needed, while the system maintains optimized resource utilization through prioritized scheduling and conditional access mechanisms
Data Source
AI summary
A method for sending a media access control control element includes: triggering, by a UE, generation of a MAC CE used for a BFRQ; determining a latest available uplink resource for new transmission; and sending, on the uplink resource, a generated MAC CE used for the BFRQ.