Crest Factor Reduction Core Using Digital Filter
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing repeater technologies face inefficiencies due to high peak to average power ratio (PAPR), which increases delay time and limits power amplifier efficiency, particularly with crest factor reduction (CFR) methods.
Innovation Solution
A method and device utilizing a CFR core with a clipper, delay unit, error shaping filter, digital filter, and subtractors to reduce PAPR, where the digital filter replaces the delay unit, minimizing delay time and PAPR.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If a delay unit is used in the CFR core, then PAPR reduction is achieved, but delay time increases
Solution Approach 1:
The patent replaces the delay unit with a digital filter that changes the processing parameters. Instead of introducing a fixed time delay, the digital filter processes the signal through filtering operations that achieve PAPR reduction without the same time penalty. This parameter change from time-based delay to filter-based processing resolves the contradiction between PAPR reduction and delay time minimization.
2Use of energy by moving object
If crest factor reduction (CFR) methods are applied, then power amplifier efficiency is improved, but delay time increases
Solution Approach 1:
The patent substitutes the traditional delay-based CFR mechanism with a digital filtering approach. The digital filter (including error shaping filter and noise cancellation filter) replaces the mechanical/time-based delay system, achieving the same PAPR reduction effect that improves power amplifier efficiency while avoiding the delay time penalty associated with traditional delay units.
Data Source
AI summary
According to an aspect of the inventive concept, there is provided a crest factor reduction (CFR) core, including: a clipper clipping an input signal; a delay unit delaying the input signal; a first subtractor subtracting the clipped input signal from the delayed input signal; an error shaping filter filtering the subtracted signal for shaping an error which occurs by the clipping of the input signal; a digital filter filtering the input signal for cancelling noise of the input signal; and a second subtractor subtracting the filtered subtracted signal from the filtered input signal.