Wireless Power Amplifier Modeling With Piecewise Nonlinear Correction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing non-linear modeling techniques for communication devices, such as power amplifiers, face challenges in efficiently operating in non-linear regions due to high computational costs and errors associated with high-order non-linear terms, which can lead to device failure in meeting regulatory specifications and complicate matrix operations.
Innovation Solution
The method involves obtaining a sample of power consumption signals from devices operating in non-linear ranges, computing corrections based on non-overlapped non-linear sections, and applying these corrections to adjust the driving signals to desired power levels, using third-order spline models and vectorial methods to reduce model order and avoid complex calculations like square root and arctan computations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If high-order non-linear terms are used to model non-linear devices, then modeling accuracy is improved, but computational complexity increases
Solution Approach 1:
The patent divides the non-linear device operation range into multiple non-overlapping sections. Each section is modeled using low-order polynomials (third-order or lower) rather than attempting to model the entire range with a single high-order polynomial. This segmentation approach reduces the computational complexity of each local model while collectively maintaining high modeling accuracy across the full operating range.
Solution Approach 2:
The patent changes the modeling parameters by using different polynomial orders for different operating sections. Instead of using a consistently high-order polynomial across all operating conditions, the polynomial order is adapted to be lower (third-order or lower) for each local section, reducing computational burden while maintaining accuracy through the piecewise approach.
2Use of energy by moving object
If devices are driven hard to maximize power usage, then energy efficiency is improved, but non-linear effects increase causing specification failures
Solution Approach 1:
The patent implements a feedback mechanism where the output of the non-linear device is measured and fed back to adjust the input driving signal. The piecewise polynomial model predicts the non-linear behavior, and the feedback loop applies corrections to the input signal to compensate for these non-linearities, ensuring that the output meets regulatory specifications even when the device is driven at high power levels for maximum energy efficiency.
3Measurement precision
If high-order non-linear terms are computed, then modeling precision is improved, but matrix operations become ill-conditioned
Solution Approach 1:
By segmenting the operating range into multiple sections and using low-order polynomials for each section, the patent avoids constructing large matrices with high-order terms that would be ill-conditioned. Each local low-order model results in well-conditioned matrices that are numerically stable and easy to invert, eliminating the matrix conditioning problems associated with global high-order polynomial models.
Data Source
AI summary
Various communication devices may benefit from the appropriate use of modeling techniques. For example, devices that include components that may be driven into non-linear ranges of operation may benefit from low complexity non-linear modelling techniques. Such devices may be used, for example, in wireless communication systems. A method can include obtaining a sample of a signal representative of power consumed by a device while the device is operating in a non-linear range while being driven according to a driving signal. The method can also include computing a correction to the driving signal based on the sample. The correction can be calculated based on a plurality of non-overlapped non-linear sections corresponding to a response of the device. The method can further include applying the correction to adjust the driving signal. The correction can be configured to adjust the power to a desired value of power.