Time-Varying Perfect Reconstruction Filter Banks for Finite Length Signals
نویسندگان
چکیده
A new approach to the non-expansive two band decomposition of finite length signals is introduced. The technique is based on the time-varying perfect reconstruction filter banks concept. In this approach the main analysis filter bank is instantaneously switched, at the signal boundaries, to a shorter filter bank: the D1 or Haar filter bank. The technique can be applied to all types of two band perfect reconstruction filter banks. A low complexity design method for the required reconstruction transition filters is presented. In opposition to other types of time-varying filter banks, the proposed analysis filter bank has good low pass and high pass characteristics.
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