A hybrid method for the design of oversampled uniform DFT filter banks

Ka Fai Cedric Yiu, Nedelko Grbić, Sven Nordholm, Kok Lay Teo

Research output: Journal article publicationJournal articleAcademic researchpeer-review

12 Citations (Scopus)


Subband adaptive filters have been proposed to speed up the convergence and to lower the computational complexity of time domain adaptive filters. However, subband processing causes signal degradations due to aliasing effects and amplitude distortions. This problem is unavoidable due to further filtering operations in subbands. In this paper, the problem of aliasing effect and amplitude distortion is studied. The prototype filter design problem is formulated as a multi-criteria optimization problem and all the Pareto optima are sought. Since the problem is highly nonlinear and nonsmooth, a new hybrid optimization method is proposed. Different prototype filters are used and their performances are compared. Moreover, the effect of the number of subbands, the oversampling factors and the length of prototype filter are also studied. We find that prototype filters designed via Kaiser or Dolph-Chebyshev window provide the best overall performance. Also, there is a critical oversampling factor beyond which the improvement in performance is not justified. Finally, if the length of the prototype filter increases with the number of subbands, an increase in the subband level will not deteriorate the performance.
Original languageEnglish
Pages (from-to)1355-1364
Number of pages10
JournalSignal Processing
Issue number7
Publication statusPublished - 1 Jul 2006
Externally publishedYes


  • Aliasing effect
  • Amplitude distortion
  • Pareto optimum
  • Simulated annealing
  • Subband adaptive filter

ASJC Scopus subject areas

  • Signal Processing
  • Electrical and Electronic Engineering

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