Power Headroom Reporting for Carrier Aggregation Scheduling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In multi-carrier wireless communication systems, the base station lacks accurate maximum transmission power values for each component carrier, leading to uncertain uplink scheduling and inefficient power management.
Innovation Solution
A method and apparatus for user equipment (UE) to transmit power headroom information, including the maximum transmission power value for each component carrier, allowing the base station to accurately determine and manage power allocation across multiple carriers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional power headroom reporting is used in multi-carrier systems, then the reporting mechanism is simple, but the base station cannot accurately know the maximum transmission power value for each carrier
Solution Approach 1:
The patent segments the power headroom reporting into separate components: a first power headroom value representing the difference between maximum and estimated transmission power, and a second power headroom value representing the estimated transmission power itself. This segmentation allows the base station to accurately determine the maximum transmission power value by combining these two components, resolving the contradiction between measurement precision and device complexity.
Solution Approach 2:
The patent introduces an intermediary reporting structure where the user equipment transmits both the first power headroom value and the second power headroom value as intermediate components. The base station then uses these intermediary values to calculate the maximum transmission power value, enabling accurate measurement without requiring direct complex reporting of the maximum power itself.
2Reliability
If power headroom information is reported for each carrier individually, then carrier-specific power control is improved, but uplink scheduling becomes uncertain when multiple carriers are involved
Solution Approach 1:
The patent merges the power headroom reporting for multiple carriers into a unified structure where the user equipment reports power headroom values for each activated serving cell. The base station combines these individual carrier reports to determine the overall maximum transmission power value, which then enables reliable uplink scheduling across all carriers while maintaining carrier-specific power control capabilities.
Solution Approach 2:
The patent establishes a feedback mechanism where the user equipment continuously reports power headroom information to the base station, enabling the base station to adjust uplink scheduling decisions based on real-time power availability. This feedback loop improves uplink scheduling reliability by ensuring the base station has accurate, up-to-date information about the user equipment's power capabilities across all carriers.
3Productivity
If the base station schedules uplink transmission power without accurate maximum transmission power values, then the scheduling process is faster, but power management efficiency decreases
Solution Approach 1:
The patent implements preliminary action by having the user equipment report power headroom values in advance before uplink scheduling is needed. The base station receives and processes these preliminary power headroom reports to determine the maximum transmission power value, which then enables efficient power management during subsequent uplink scheduling operations without requiring time-consuming real-time measurements.
Solution Approach 2:
The patent applies self-service by having the user equipment autonomously calculate and report its own power headroom values based on its maximum transmission power and estimated transmission power. This self-service approach eliminates the need for the base station to perform complex power measurements, improving power management efficiency while minimizing the time required for power headroom reporting.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A method of transmitting a power headroom (PH) by a user equipment (UE) in a multi-carrier system is provided. The method includes: receiving power determination information from a base station (BS); determining a plurality of maximum transmission power values for a plurality of serving cells by using the power determination information and a UE specific parameter; determining a plurality of PHs on the basis of the plurality of maximum power transmission values; and transmitting the plurality of maximum transmission power values and the plurality of PHs to the BS. Accordingly, since the maximum transmission power value and the power headroom information are provided to the BS, reliable carrier aggregation scheduling can be induced, thereby being able to improve uplink transmission capability.