Multi-Carrier Cubic Metric Calculation for PA Distortion Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wireless communication systems face challenges in accurately calculating the cubic metric for dual-carrier and multi-carrier scenarios, particularly due to power imbalances and differences in beta-values between carriers, which affect power amplifier performance and lead to distortion.
Innovation Solution
A method and apparatus for calculating the cubic metric by adjusting gain values using a parameter derived from the power levels and gain values of multiple carriers, where the adjustment factor accounts for the relative power and amplitude differences between carriers, ensuring accurate computation of the cubic metric for power amplifier optimization.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If dual-carrier or multi-carrier operation is implemented to increase bandwidth and throughput, then communication capacity and data rate are improved, but power amplifier non-linearity distortion increases due to power imbalances and beta-value differences between carriers
Solution Approach 1:
The patent modifies the traditional single-carrier cubic metric calculation by introducing multi-carrier specific parameters including power levels (Pn) for each carrier, beta-values (βn) representing gain values for code channels on each carrier, and the number of code channels (Ln) per carrier. These parameter changes enable the cubic metric to accurately reflect the actual signal characteristics in multi-carrier scenarios, allowing the power amplifier to operate more efficiently with reduced distortion.
Solution Approach 2:
The patent segments the cubic metric calculation into carrier-specific components, where each carrier's contribution to the overall cubic metric is calculated separately based on its own power level, beta-values, and code channel configuration. This segmentation approach allows for precise modeling of power imbalances and gain differences between carriers, enabling targeted optimization of each carrier's power allocation to minimize overall distortion.
2Power
If power levels are increased on multiple carriers to maximize throughput, then communication performance is improved, but the cubic metric calculation becomes inaccurate due to power imbalances, leading to suboptimal power amplifier operation
Solution Approach 1:
The patent introduces power level parameters (Pn) for each carrier into the cubic metric calculation, replacing the assumption of equal power distribution. This parameter change allows the cubic metric to accurately capture the actual power distribution across carriers, enabling precise measurement of the signal's impact on power amplifier non-linearity even when power levels are maximized on multiple carriers.
3Reliability
If different beta-values are assigned to different carriers to optimize individual carrier performance, then carrier-specific quality of service is improved, but the traditional cubic metric computation fails to account for inter-carrier variations, resulting in inaccurate distortion prediction
Solution Approach 1:
The patent applies local quality by allowing each carrier to have its own beta-values (βn) specific to its code channels, rather than using a single set of beta-values for all carriers. This enables each carrier to be optimized for its specific QoS requirements while the cubic metric calculation accounts for these local variations. The patent further refines this by introducing carrier-specific gain adjustments that consider both the beta-values and power levels of individual carriers.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
In accordance with an example embodiment of the present invention, a method is disclosed that comprises receiving at least two sets of gain values, wherein each set of gain values denotes the gains of a set of code channels that are carried by each of at least two carriers; receiving at least two power or amplitude levels that are allocated to the at least two carriers; and calculating a cubic metric based on the received at least two sets of gain values and the received at least two power or amplitude levels.