Ghosh Prasanta Kumar, Narayanan Shrikanth S
Signal Analysis and Interpretation Laboratory, Department of Electrical Engineering, University of Southern California, Los Angeles, CA 90089, Ph: (213) 821-2433.
IEEE Signal Process Lett. 2010 Mar;17(6):543-546. doi: 10.1109/LSP.2010.2046192.
We propose an arbitrary order stable allpass filter structure for frequency transformation from Hertz to Bark scale. According to the proposed filter structure, the first order allpass filter is causal, but the second and higher order allpass filters are non-causal. We find that the accuracy of the transformation significantly improves when a second or higher order allpass filter is designed compared to a first order allpass filter. We also find that the RMS error of the transformation monotonically decreases by increasing the order of the allpass filter.
我们提出了一种用于从赫兹到巴克尺度频率变换的任意阶稳定全通滤波器结构。根据所提出的滤波器结构，一阶全通滤波器是因果的，但二阶及更高阶全通滤波器是非因果的。我们发现，与一阶全通滤波器相比，设计二阶或更高阶全通滤波器时，变换的精度会显著提高。我们还发现，通过增加全通滤波器的阶数，变换的均方根误差会单调减小。
