A Construction of M-Channel Filter Banks with Hilbert Transformers.

This paper proposes a new design method for the filter bank. The filter bank is a system which can reconstruct a signal via band-splitting, decimation, interpolation and restoration. It is employed widely to solve various problems in the communication system, and various methods have been presented for its specification, implementation and design. This paper discusses the approximate realization of the filter bank, which is called the M-channel uniform-splitting FIR perfect-reconstruction filter bank, and its design principle is as follows. First, the analysis filter is designed so that each channel has the characteristic which is the translation of the given LPF on the frequency axis. Then the synthesis filter is designed in the time-domain so that the unit impulse response of the whole system is equivalent to the unit pulse, i.e., that the response of the linear-phase all-pass transmission characteristic. The Hilbert transformer plays the important role in the translation of the characteristic. Compared with the conventional design, the proposed method has the merit that no constraint is imposed on the band splitting and the band is partitioned uniformly with an arbitrary number of divisions. Design examples are shown to indicate the usefulness of the proposed design. [ABSTRACT FROM AUTHOR]