Multi-CC Transmit Power Control for LTE Uplink
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In Long Term Evolution (LTE) wireless communication systems, managing transmit power across multiple component carriers (CCs) is challenging, particularly in maintaining power within limits to avoid overloading power amplifiers and reducing inter-cell interference, especially with features like carrier aggregation and simultaneous PUSCH and PUCCH transmissions.
Innovation Solution
A method and apparatus for determining transmit power for each channel mapped to multiple CCs, including autonomously limiting the power difference between CCs to ensure the power amplifier operates within its linear region and comply with maximum transmit power limits, by adjusting the power of each CC independently or jointly based on channel priorities and power differences.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If transmit power is increased to maintain quality of service and compensate for pathloss, then communication reliability is improved, but power amplifier overload and inter-cell interference increase
Solution Approach 1:
The patent segments the transmit power control into separate components for each component carrier (CC), allowing independent power adjustment for each CC while sharing a common power amplifier. This enables the system to optimize power for each carrier without causing overall PA overload or excessive inter-cell interference.
Solution Approach 2:
The patent changes the power transmission parameter dynamically based on channel conditions, pathloss measurements, and interference levels. By adjusting transmit power on a per-CC basis and modifying power reduction factors, the system maintains QoS while controlling harmful interference effects.
2Reliability
If transmit power is increased to compensate for pathloss, then communication reliability is improved, but power amplifier overload occurs
Solution Approach 1:
The patent segments the total transmit power into separate power components for each component carrier, allowing the system to distribute power across multiple CCs rather than concentrating all power on a single carrier. This prevents PA overload while maintaining communication reliability through coordinated multi-CC transmission.
Solution Approach 2:
The patent applies partial power transmission on each individual CC rather than full power on all CCs simultaneously. By using power reduction factors and selective power allocation, the system achieves sufficient reliability without exceeding PA power capabilities.
3Productivity
If multiple component carriers are used to extend bandwidth, then system capacity is improved, but power management complexity increases
Solution Approach 1:
The patent segments the power management task into separate control mechanisms for each CC, with each CC having its own power adjustment parameters. This segmentation allows the system to handle multiple CCs independently while maintaining overall power control, thus managing complexity despite increased capacity.
Solution Approach 2:
The patent creates a universal power control framework that handles multiple CCs through a common power amplifier shared by all carriers. This multi-functional approach allows the same PA to serve multiple purposes across different CCs, reducing overall system complexity compared to having separate PAs for each carrier.
4Reliability
If maximum power procedure is used to ensure transmit power limits are met, then regulatory compliance is improved, but power amplifier linear region operation is violated
Solution Approach 1:
The patent dynamically adjusts transmit power levels based on real-time channel conditions, pathloss measurements, and PA operating status. Rather than using a static maximum power procedure, the system continuously optimizes power to maintain linear PA operation while meeting regulatory requirements through adaptive power control.
Data Source
Figure 1A
Figure 1B
Figure 1C
AI summary
A method and apparatus for controlling or determining transmit power of transmissions on more than one component carrier (CC) is disclosed. A WTRU may set a transmit power for each of a plurality of channels mapped to multiple CCs. The channels may include at least one physical uplink shared channel (PUSCH) and may also include at least one physical uplink control channel (PUCCH).