Scheduling Request Processing in NTN With Uplink Synchronization Checks
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In scenarios where a terminal device is out of uplink synchronization, existing methods for processing scheduling requests (SR) result in power waste and resource inefficiency due to the initiation of random access procedures or SR transmission, which cannot be successfully received by the access network.
Innovation Solution
Implement a method where the terminal device sends an SR only when it has a valid PUCCH resource and receives no uplink synchronization loss indication, thereby preventing SR transmission in out-of-synchronization states to conserve power and resources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the terminal device sends SR when it has a valid PUCCH resource but is out of uplink synchronization, then the SR transmission can be performed, but the access network device cannot successfully receive the SR due to loss of uplink synchronization
Solution Approach 1:
The terminal device checks uplink synchronization status before sending SR. By performing this check in advance (preliminary action), the device prevents sending SR when out of synchronization, avoiding both failed reception and unnecessary power consumption. The synchronization check is performed prior to the SR transmission decision.
Solution Approach 2:
The system uses uplink synchronization status as feedback to control SR transmission. The terminal device monitors synchronization state and uses this feedback information to determine whether to send SR, ensuring that SR is only transmitted when the uplink synchronization status indicates successful reception conditions.
2Reliability
If the terminal device initiates random access procedure when out of uplink synchronization, then the device can attempt to re-establish synchronization, but this consumes additional time and resources that could be avoided
Solution Approach 1:
The terminal device checks uplink synchronization status before initiating random access procedure. By performing this check in advance, the device avoids unnecessary random access when already synchronized, reducing access latency while still enabling timely synchronization recovery when needed.
Solution Approach 2:
Instead of always initiating random access procedure, the terminal device performs a partial check (synchronization status verification) before committing to the full random access procedure. This partial action filters out cases where random access is unnecessary, reducing overall access latency.
3Ease of operation
If the terminal device sends SR without checking synchronization status, then the transmission process is simplified, but the access network device cannot successfully receive the SR when the device is out of synchronization
Solution Approach 1:
A synchronization status check is performed as a preliminary action before SR transmission. This simple check does not complicate the overall SR transmission process significantly but ensures that SR is only sent when reception conditions are met, maintaining both simplicity and reliability.
4Reliability
If the terminal device continuously monitors uplink synchronization status, then the device can avoid sending SR when out of synchronization, but this increases device complexity and processing overhead
Solution Approach 1:
Instead of continuous monitoring, the terminal device performs a partial check of synchronization status only at critical decision points (before SR transmission and before random access initiation). This reduced monitoring approach maintains synchronization awareness where needed while minimizing processing overhead.
Data Source
AI summary
A scheduling request processing method and apparatus are applicable to a non-terrestrial network NTN scenario. The method includes: A first entity determines that a first scheduling request SR in a pending state exists. When a first condition is satisfied, the first entity indicates a second entity to send the first SR. The first condition includes: The first entity has an SR transmission occasion on a valid physical uplink control channel PUCCH resource for SR configured, and the first entity receives no uplink synchronization loss indication. Based on this solution, when the first entity has the SR transmission occasion on the valid PUCCH resource for SR configured, to indicate the second entity to send the first SR, at least a condition that the first entity receives no uplink synchronization loss indication needs to be satisfied.