ALLPASS-BASED DUAL-NOTCH FILTER WITH CLOSELY SPACED NOTCH FREQUENCIES
Abstract
In this paper, the method for designing a digital filter with two closely spaced notch frequencies is presented. The filter is implemented using two all-pass filters connected in parallel. To achieve an approximately linear phase, one of the all-pass filters is a pure delay. The proposed configuration, consisting of two IIR all-pass filters, can provide two notch frequencies and a flexible phase response. Unlike a filter of the same configuration with a piecewise-constant phase, where the filter order is 4 to realize two notch frequencies, the described approach for designing an approximately linear-phase filter allows increasing the filter order to reduce the approximation error.
Fields of Study & Subjects
Digital Filter Design and Implementation
Advanced Adaptive Filtering Techniques
Analog and Mixed-Signal Circuit Design
Publication details
- Journal / source
- Horizons - International Scientific Journal
- Volume
- 3
- Issue
- 1
- Pages
- 7–28
- Publication date
- 26 February 2026
- Language
- EN