SMTC2-LP Configuration for 5G UE Power Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In wireless communication systems, particularly in 5G NR networks, the overlapping periodicities of SMTC and SMTC2-LP configurations for inter-frequency and intra-frequency carriers can lead to resource inefficiencies and power consumption issues, making it challenging for user equipment (UE) to perform simultaneous cell measurements and paging receptions during idle or inactive modes.
Innovation Solution
The implementation of SMTC2-LP configurations allows for less frequent SSB bursts, enabling UE to selectively use either SMTC or SMTC2-LP periodicities based on available configurations, thereby optimizing resource usage and power consumption by canceling unnecessary measurements and aligning with DRX cycles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If SMTC and SMTC2-LP configurations are used for cell measurements in idle/inactive modes, then measurement capability is improved, but overlapping periodicities cause resource inefficiency and increased power consumption
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the periodicity of SMTC occasions based on UE state (idle vs. connected) and configuration type. SMTC2-LP uses a longer periodicity (e.g., 160ms) compared to standard SMTC, reducing the frequency of synchronization signal block measurements during idle periods when mobility requirements are lower, thereby decreasing power consumption while maintaining adequate measurement capability.
Solution Approach 2:
The system dynamically selects between different SMTC configurations (standard SMTC vs. SMTC2-LP) based on current operational conditions. The gNB can configure different periodicities and the UE adapts its measurement behavior accordingly, switching between more frequent measurements when needed and less frequent measurements to conserve power when in idle state, making the measurement system flexible and condition-dependent.
2Measurement precision
If SMTC occasions are configured with standard periodicity, then measurement accuracy is maintained, but resource overhead increases and conflicts with DRX cycles
Solution Approach 1:
The patent changes the periodicity parameter of SMTC occasions from standard values to extended values (SMTC2-LP with longer periods). This reduces the number of synchronization signal blocks that need to be transmitted and measured, thereby reducing resource overhead in terms of time-frequency resources and UE processing burden, while still maintaining sufficient measurement accuracy for idle/inactive mode requirements.
3Reliability
If simultaneous cell measurements and paging receptions are performed, then communication reliability is improved, but overlapping SMTC periodicities create measurement conflicts
Solution Approach 1:
The patent uses periodic action by aligning SMTC2-LP occasions with DRX cycles through carefully selected periodicities. The extended periodicity of SMTC2-LP (e.g., 160ms) can be made to coincide with or be a multiple of DRX cycle lengths, creating a harmonized periodic schedule that reduces conflicts between measurement activities and paging receptions, simplifying the scheduling complexity while maintaining reliability.
Data Source
AI summary
Systems and methods disclosed herein describe the use of synchronization signal/physical broadcast channel block measurement time configuration (SMTC) 2 low power (SMTC2-LP) configuration(s). For cell measurements, a UE may determine that an SMTC2-LP configuration for one or more carriers of one or more target cells is known, determine a periodicity of SMTC occasions of the carrier(s) based on data found in the SMTC2-LP configuration(s), and cancel a cell measurement of an inter-frequency cell based at least in part on the periodicity of the SMTC occasion(s). For cell re-selection, a UE may determine that an SMTC2-LP configuration for a carrier being used at a target cell is known and that a physical cell identity (PCI) of the target cell is found in data of the SMTC2-LP configuration, determine a maximum paging interruption time using this periodicity, and perform a cell reselection to the target cell within this time.