In this paper a detailed analysis of an atypical filter structure in MATLAB Filter Design and Analysis (FDA) Tool is presented. As an example of
atypical filter structure, the IIR half-band filter with approximately
linear phase realized as a parallel connection of two all-pass branches was
examined. We compare two types of those filters obtained by two different
design algorithms. FDA tool was used for the experiment because different
effects of the fixed point implementation can be simulated easily. One of
the goals of this paper was to compare results obtained by two different
design algorithms. In addition, different realizations of the filter
structure based on the parallel connection of two all-pass branches were
examined.