Terminal Random Access Control Across Candidate Cells
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In future radio communication systems, controlling uplink transmission during inter-cell mobility, particularly when switching between a serving cell and a candidate cell, is challenging due to unclear methods for random access procedures, which can degrade communication quality if not appropriately managed.
Innovation Solution
A terminal equipped with a receiving section for downlink control channels to trigger random access preambles for multiple candidate cells, and a control section to judge which cells to transmit based on response signals, enabling appropriate control of inter-cell mobility through monitoring of response signals or lack thereof.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If inter-cell mobility is implemented with multiple candidate cells for random access procedures, then communication flexibility and mobility performance are improved, but control complexity and uncertainty in uplink transmission management increase
Solution Approach 1:
The patent segments the candidate cells into two distinct groups: first candidate cells that monitor for random access response (RAR) and second candidate cells that do not monitor for RAR. This segmentation resolves the control complexity by providing clear, differentiated procedures for each cell type, eliminating uncertainty about which procedure to use while maintaining the flexibility of supporting multiple candidate cells for inter-cell mobility.
Solution Approach 2:
The patent introduces dynamic control mechanisms where the network can flexibly configure and switch between different random access procedures (with RAR monitoring and without RAR monitoring) based on current communication conditions. This dynamic approach allows the system to adapt to varying mobility scenarios while maintaining manageable control complexity through standardized procedural frameworks.
2Adaptability or versatility
If random access procedures are performed for candidate cells without clear control methods, then inter-cell mobility capability is enhanced, but communication quality deteriorates due to improper procedure execution
Solution Approach 1:
The patent establishes preliminary, well-defined control methods for random access procedures before inter-cell mobility is executed. By pre-specifying which candidate cells should monitor for RAR and which should not, the system eliminates execution uncertainty and ensures proper procedure performance, thereby maintaining communication quality while enabling mobility capability.
Solution Approach 2:
The patent implements feedback mechanisms through RAR monitoring for first candidate cells, where the network provides explicit responses to confirm successful random access. This feedback ensures reliable procedure execution and allows for error correction, maintaining communication quality while enabling flexible inter-cell mobility through controlled feedback loops.
Data Source
Figure 1A~1B
Figure 2
Figure 3A~3B
AI summary
A terminal according to one aspect of the present disclosure includes a receiving section that receives a downlink control channel supporting triggering of a random access preamble (PRACH) for a plurality of candidate cells, and a control section that judges, based on the downlink control channel, one or more candidate cells for which transmission of the PRACH is performed. The plurality of candidate cells include a first candidate cell with monitoring of a response signal (RAR) to the PRACH and a second candidate cell without monitoring of an RAR to the PRACH.