On Implementation and Design of Filter Banks for Subband Adaptive Systems
نویسنده
چکیده
In this paper, we introduce a polyphase implementation and design of an oversampled K-channel generalized DFT (GDFT) l-ter bank, which can be employed for subband adaptive ltering, and therefore is required to have a low aliasing level in the subband signals. A polyphase structure is derived which can be factorized into a real valued polyphase network and a GDFT modulation. For the latter, an FFT realization may be used, yielding a very inexpensive polyphase implementation for arbitrary integer decimation ratios N K. We also present an analysis underlining the eeciency of complex valued subband processing. The design of the lter bank is completely based on the prototype lter and solved using a fast converging iterative least squares method, for which we give examples. The design speciications closely correspond with performance limits of subband adaptive ltering, which are underpinned by simulation results.
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