Recent Advances in Variable Digital Filters

  title={Recent Advances in Variable Digital Filters},
  author={Shunsuke Koshita and Masahide Abe and Masayuki Kawamata},
Variable digital filters are widely used in a number of applications of signal processing because of their capability of self-tuning frequency characteristics such as the cutoff frequency and the bandwidth. This chapter introduces recent advances on variable digital filters, focusing on the problems of design and realization, and application to adaptive filtering. In the topic on design and realization, we address two major approaches: one is the frequency transformation and the other is the… Expand
The Phase Response Values Application of Second-Order Digital Frequency-Dependent Components for Calculating Transfer Function Coefficients in Robotic Systems
The obtained approximations of phase frequency responce dependence on the ripple level allowed us to find the digital filter transfer function of the denominator coefficients values, and to obtain the three-dimensional graph approximation. Expand
The Phase-Frequency Response Influence on the Tunable Frequency-Dependent Component Coefficients
The obtained approximations of PFR dependence on the ripple level allowed us to find the digital filter transfer function of the denominator coefficients values that contributes to a more rapid rearrangement of their characteristic responses when built in the platforms with limited computing and energy resources. Expand
Specialized Computer Systems Digital Bandpass Frequency-Dependent Components Rearrangement
Equations are found allowing to determine definitely these coefficients at given cut-off frequencies, which provides a significant facilitation of rearrangement task. Expand


Design of recursive digital filters with variable characteristics
A new method for changing the cut-off frequency of infinite impulse response (IIR) digital filters with a single parameter is derived. the method is based on the use of the Taylor series expansion ofExpand
A design technique for variable digital filters
A design technique for variable filters with coefficients that are directly computable from the specified spectral parameters is proposed, which expresses the frequency specifications by using a curve-fitting technique. Expand
Variable Digital Filters
An attempt is made to review and systematize all known structures and methods of design of variable digital filters with variable characteristics for different applications. Expand
A Design Method for Variable Linear-Phase FIR Filters with Changing Multifactors for Checkweighers
  • T. Miyata, N. Aikawa
  • Mathematics, Computer Science
  • IEICE Trans. Fundam. Electron. Commun. Comput. Sci.
  • 2010
This paper presents a design method for variable linear-phase finite impulse response (FIR) filters with multiple variable factors and a reduction method for the number of polynomial coefficients and presents that the proposed VDF can be implemented using the Farrow structure, which suitable for real time signal processing. Expand
Synthesis of variable IIR digital filters with complex coefficients
Sometimes it is required to change the filter characteristics of a digital filter in real time during its filtering operation. To meet this requirement, variable cutoff frequency lowpass filters withExpand
A continuously variable digital delay element
  • C. Farrow
  • Computer Science
  • 1988., IEEE International Symposium on Circuits and Systems
  • 1988
An FIR (finite-impulse-response) filter which synthesizes a controllable delay which has the ability to interpolate between samples in the data stream of a band-limited signal is described. Expand
Recursive center-frequency adaptive filters for the enhancement of bandpass signals
  • R. Kumar, R. Pal
  • Computer Science
  • IEEE Trans. Acoust. Speech Signal Process.
  • 1986
A new adaptive algorithm, namely, the recursive maximum-mean-squares (RMXMS) algorithm, is developed based on the gradient ascent technique for the implementation of these filters. Expand
Tracking of bandpass signals using center-frequency adaptive filters
The tracking performance of two examples of these filters are analyzed for step, ramp, and sinusoidal variations of the input signal center frequency, and these are shown to track the signals very effectively. Expand
A new method for designing FIR filters with variable characteristics
This letter proposes a new method for designing finite-impulse response (FIR) filters with variable characteristics that is simple and effective in designing FIR VDF with good frequency characteristics and allows for more complicated frequency characteristics or a larger tuning range to be approximated. Expand
On linear-phase FIR filters with variable bandwidth
It is demonstrated that the use of a number of fixed regular overdesigned filters, each taking care of a part of the frequency region, in fact results in a lower overall arithmetic complexity. Expand