Polar RF Phase Path Calibration for Distortion Pre-Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Polar architecture radio frequency systems experience additional phase path distortions due to separate amplitude and phase paths, leading to inefficient and inaccurate wireless data transmission.
Innovation Solution
A calibration feedback loop down-converts processed signals to baseband, allowing calibration logic to calculate an inverse kernel for phase path distortion, which is then used by pre-distortion logic to invert phase path nonlinearity, reducing phase path distortions and improving transmission efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If a polar architecture with separate AM and PM paths is used to enhance transmission efficiency, then power efficiency is improved, but additional phase path distortions (PM-to-AM and PM-to-PM distortions) are introduced
Solution Approach 1:
The patent applies preliminary action by pre-distorting the phase path signal in advance to counteract the expected distortions that will occur in the polar architecture. The pre-distortion logic modifies the phase signal before it enters the polar modulator, preparing it to compensate for the PM-to-AM and PM-to-PM distortions that will be introduced by the separate AM and PM paths. This allows the system to maintain high power efficiency while reducing the net distortion at the output.
Solution Approach 2:
The patent implements feedback through a calibration loop that measures the actual distortions produced by the polar architecture and uses this information to adjust the pre-distortion parameters. The feedback mechanism allows the system to adapt to varying distortion conditions and optimize the pre-distortion compensation, ensuring that the phase path distortions are effectively cancelled while maintaining the power efficiency benefits of the polar architecture.
2Measurement precision
If pre-distortion logic is added to reduce phase path distortions, then transmission accuracy is improved, but device complexity increases
Solution Approach 1:
The patent applies segmentation by dividing the distortion compensation function into separate dedicated modules: pre-distortion logic for the phase path, calibration logic for measuring distortions, and combination logic for merging the corrected signals. This modular approach allows each component to be optimized independently and simplifies the overall system architecture, reducing the complexity burden that would otherwise result from a monolithic distortion compensation system.
Solution Approach 2:
The patent implements multi-functionality by designing the pre-distortion logic and calibration logic to handle multiple types of distortions (PM-to-AM and PM-to-PM) within a unified framework. The same computational structures are used to address different distortion mechanisms, reducing the need for separate dedicated circuits for each distortion type and thereby limiting the increase in device complexity while maintaining high transmission accuracy.
Data Source
AI summary
Systems and method provided herein relate to reducing distortion of signals introduced by components on a phase path of a radio frequency system polar architecture. To reduce phase path distortion, a pre-distortion is introduced prior to a distortion caused by the components on the phase path. The pre-distortion in conjunction with the component distortion results in a transmission signal that forms its expected shape.