Coherent Multi-Band Peak Detection Using Phase Information
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Peak Cancellation algorithms for Multi-Standard Radio transmitters fail to accurately detect peaks in multi-band signals, leading to overestimation of signal amplitudes and increased Error Vector Magnitude (EVM) due to neglecting phase information, resulting in inefficient Power Amplifier performance.
Innovation Solution
A method for detecting peaks in multi-band transmit signals that involves receiving and processing multiple band input signals, taking into account phase information, by upsampling, summing, and frequency translating the signals to accurately combine them, allowing for coherent peak detection and reducing Peak-to-Average Ratio (PAR) without excessive clipping.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If peak detection is performed without considering phase information of multiple band signals, then the detection process is simpler and faster, but the peak amplitude is overestimated leading to increased EVM
Solution Approach 1:
The patent applies preliminary action by performing upsampling of the multiple band signals before peak detection. This preprocessing step increases the sampling rate to ensure that peak instances are captured accurately, and by incorporating phase information in this preliminary stage, the subsequent peak detection can proceed with higher accuracy without excessive complexity during the detection itself.
Solution Approach 2:
The patent segments the multi-band signal processing into distinct stages: upsampling individual band signals, frequency translating them to a common reference, and then combining them for peak detection. This segmentation allows phase information to be properly accounted for in each stage, improving peak detection accuracy while managing computational complexity through structured processing.
2Use of energy by moving object
If signal amplitude is limited to a chosen threshold to reduce PAR, then the Peak-to-Average Ratio is reduced, but out-of-band spectrum emissions increase due to clipping distortion
Solution Approach 1:
The patent employs feedback by using the detected peak information to generate compensation signals that are subtracted from the original multi-band signal. This feedback mechanism allows for precise peak cancellation that reduces PAR while minimizing clipping distortion, thereby reducing out-of-band emissions compared to simple threshold limiting.
Solution Approach 2:
The patent changes the parameter of peak detection by incorporating phase information and performing detection at higher sampling rates. This parameter change enables more accurate identification of true peak instances and amplitudes, allowing the CFR algorithm to apply more precise amplitude limiting that reduces PAR while minimizing the harmful clipping effects that cause out-of-band emissions.
3Measurement precision
If multiple band signals are combined without frequency translation and upsampling, then the processing is faster and simpler, but peak detection accuracy decreases due to sampling rate insufficiency
Solution Approach 1:
The patent performs upsampling and frequency translation as preliminary actions before peak detection. By increasing the sampling rate in advance, the system ensures that peak instances are captured with sufficient resolution. This preliminary processing, while adding computational steps, enables accurate peak detection without requiring continuous high-rate processing throughout the entire signal chain.
Solution Approach 2:
The patent transitions to another dimension by moving the signals to a common frequency reference through frequency translation before combining them for peak detection. This dimensional change in the frequency domain allows for proper coherent combination of multiple band signals, enabling accurate peak detection that accounts for phase relationships while maintaining computational efficiency through structured transformation.
Data Source
AI summary
Systems and methods for detecting peaks in a multi-band transmit signal are disclosed. In some embodiments, a method of operation of a multi-band transmitter for detecting peaks in a multi-band transmit signal which includes multiple transmit signals on a respective multiple frequency bands includes receiving a first band input signal for a first frequency band of the multi-band transmit signal and at least one additional band input signal for a respective at least one additional frequency band of the multi-band transmit signal. The method also includes detecting a peak of a combination of the first band input signal and the at least one additional band input signal taking into account phase information of the first band input signal and the at least one additional band input signal. In this manner, the detected peak might not be overestimated as when the peak detection fails to take into account the phase information.