Dual SIM Power Headroom Reporting for Link Adaptation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In dual SIM wireless communication devices, the independent scheduling of eNodeBs leads to performance degradation in uplink link adaptation and transmit power control due to the lack of awareness of uplink transmissions on the other SIM, resulting in inefficient power utilization and fluctuations in power headroom reports.
Innovation Solution
The method modifies the power headroom report to account for the transmit power required by the other SIM in dual connectivity scenarios, and when dual connectivity is not configured, it averages the transmit power over allocated subframes to stabilize link adaptation performance, ensuring accurate resource allocation and reduced fluctuations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If independent scheduling is used for each SIM in dual SIM devices, then device complexity is reduced and ease of operation is improved, but link adaptation performance deteriorates due to lack of awareness of uplink transmissions on the other SIM
Solution Approach 1:
The patent introduces an intermediary mechanism where the UE reports power headroom information to the eNodeB, which then uses this information to adjust scheduling decisions. This mediator (power headroom report) allows the eNodeB to become aware of power constraints from other SIM transmissions without requiring direct coordination between SIMs, thus maintaining independent scheduling while improving link adaptation performance
Solution Approach 2:
The patent implements a feedback loop where the UE continuously reports power headroom status to the eNodeB, and the eNodeB uses this feedback to adjust uplink grants and scheduling decisions. This feedback mechanism enables the system to adapt to changing power conditions caused by other SIM transmissions, resolving the contradiction between independent scheduling and link adaptation performance
2Device complexity
If power headroom reports are generated independently for each SIM, then device complexity is reduced, but power utilization efficiency deteriorates due to fluctuations and lack of awareness of other SIM transmissions
Solution Approach 1:
The patent merges power headroom information from multiple SIMs into a unified report structure. Instead of generating completely separate reports for each SIM, the system combines power headroom calculations considering transmissions from all SIMs, allowing the eNodeB to make more efficient power allocation decisions while maintaining manageable device complexity through standardized reporting procedures
3Adaptability or versatility
If standard power headroom reporting is used without modifications, then compatibility with existing standards is maintained, but resource allocation reliability deteriorates due to inaccurate power information
Solution Approach 1:
The patent applies partial modification to the standard power headroom reporting mechanism. It uses the existing standard report structure and procedures but adds enhanced calculations that account for other SIM transmissions. This partial action approach maintains full standard compatibility while improving resource allocation reliability through more accurate power information in the reports
Data Source
Figure 1
Figure 2~3
Figure 4~5
AI summary
A method and apparatus for reporting power headroom to a base station in a user equipment having two subscriber identity modules (SIMs). In a user equipment with a dual connectivity SIM, the power headroom report (PHR) to a first base station includes a second power headroom value of the dual connectivity connection reduced by the power headroom value of the second SIM. The PHR to the second base station includes the first power headroom value reduced by the power headroom value of the second SIM. In a single connectivity, dual SIM user equipment, the PHR includes an average power headroom value of the other SIM.