HFC Cable Modem Non-Linear Signal Compensation
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Solution Overview
Problem
Hybrid fiber coaxial (HFC) networks face high power consumption due to multiple power amplifiers, leading to reduced linearity and severe non-linear distortion of signals received by subscribers, which affects signal quality.
Innovation Solution
A signal processing method that includes converting distorted signals into digital form, performing non-linear compensation using a compensation coefficient, and signal recovery processing to improve signal quality while reducing power consumption by optimizing power amplifier usage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If power amplifiers are used to compensate for signal attenuation in HFC networks, then signal quality is improved, but power consumption increases
Solution Approach 1:
The patent extracts the non-linear distortion compensation function from the power amplifier and implements it separately in a digital signal processing unit. This allows the power amplifier to operate at higher power levels without introducing severe non-linear distortion, thereby improving signal quality while maintaining reasonable power consumption through efficient digital compensation algorithms.
Solution Approach 2:
The patent introduces a digital signal processing unit as an intermediary between the power amplifier and the output stage. This intermediary performs non-linear distortion compensation on the amplified signal, enabling the power amplifier to operate at higher efficiency points while the intermediary corrects the resulting distortion, thus resolving the contradiction between power consumption and signal quality.
2Use of energy by moving object
If power amplifiers operate in the non-linear region to improve efficiency, then power consumption is reduced, but non-linear distortion of signals increases
Solution Approach 1:
The patent converts the harmful non-linear distortion generated by the power amplifier into a measurable and compensatable effect. By characterizing the distortion and implementing digital compensation algorithms, the system transforms the previously harmful distortion into a controlled parameter that can be corrected, allowing the power amplifier to operate efficiently in the non-linear region while maintaining signal quality.
Solution Approach 2:
The patent implements a feedback mechanism where the output signal from the power amplifier is monitored, analyzed for non-linear distortion, and then compensated through digital signal processing. This closed-loop feedback system enables the power amplifier to operate at high efficiency points while the feedback-driven compensation continuously corrects the introduced distortion, resolving the contradiction between power consumption and signal quality.
Data Source
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AI summary
Embodiments of the present invention disclose a signal processing method and a related device. The method may include: after receiving a distorted signal amplified by a power amplifier, converting, by a cable modem, the distorted signal into a digital signal, and performing non-linear compensation on the digital signal by using a compensation coefficient. In this manner, power consumption of an HFC network can be reduced and quality of a signal received by a subscriber end can be improved. Further, because quantities of times for amplifying signals received by CMs at different distances from an optical node device vary, non-linear distortion degrees of signals received by different CMs are different. In the embodiments of the present invention, a subscriber end device (namely, the CM) collectively performs compensation on a final signal, so as to improve a network service capability to some extent.