Uplink Preemption Indication for Dynamic Power and URLLC Reliability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing wireless communication systems, particularly 5G NR, face challenges in efficiently managing uplink preemption for different services with varying latency and reliability requirements, leading to interference and suboptimal resource utilization.
Innovation Solution
Implementing uplink preemption indication (ULPI) to manage resource preemption and power control, allowing UEs to adjust their transmissions based on power levels and cancellation to accommodate urgent services like URLLC, thereby reducing interference and enhancing system efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If uplink preemption indication is implemented to manage resource preemption for URLLC services, then reliability and latency performance improve, but control signaling overhead increases
Solution Approach 1:
The uplink preemption indication is segmented into multiple fields: a first field indicating power level information and a second field indicating cancellation information. This segmentation allows the gNB to convey preemption requirements in a structured manner, enabling UEs to process and apply the appropriate actions (power adjustment or transmission cancellation) without requiring complete reconfiguration of the entire control signal structure.
2Object-affected harmful factors
If dynamic power adjustment is applied based on ULPI, then interference reduction improves, but transmit power control complexity increases
Solution Approach 1:
The system implements dynamic power adjustment where the gNB can indicate different power levels (e.g., first power level and second power level) based on the specific preemption scenario. The UE dynamically selects and applies the appropriate power level according to the ULPI fields, allowing flexible interference management that adapts to varying service requirements without fixed power control configurations.
Solution Approach 2:
The power level parameter is changed dynamically based on the preemption indication. Instead of using fixed power levels, the system transitions between different power states (normal power, reduced power, or cancellation) according to the ULPI fields, enabling precise control of uplink interference while maintaining system flexibility.
3Productivity
If ULPI monitoring periodicity is extended to cover longer durations, then resource allocation efficiency improves, but response time for urgent transmissions decreases
Solution Approach 1:
The gNB sends the ULPI in advance of the actual uplink transmission time, allowing the UE to prepare and adjust its transmission parameters beforehand. This preliminary indication enables the UE to apply power adjustments or cancellations before the scheduled transmission occurs, ensuring timely response while maintaining efficient resource allocation across extended monitoring periods.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Certain aspects of the present disclosure provide techniques for uplink preemption indication. A method for wireless communication by a user equipment (UE) includes receiving at least one ULPI from a base station (BS) indicating, for each of a plurality of sets of uplink resources, a power level the UE can use for one or more uplink transmissions. The UE can determine one or more power levels indicated by the ULPI for resources allocated for the UE for uplink transmission. The allocated resources may include multiple of the sets of uplink resources. The UE can select the power level to use for uplink transmission using the allocated resources based, at least in part, on the determination. The UE sends or drops the one or more uplink transmissions according to the ULPI. A time duration of the plurality of sets of uplink resources can be longer than a configured ULPI monitoring periodicity.