Title :
Approximation of classical IIR filters with additional specifications
Author :
Dam, H.H. ; Norbedo, S. ; Svensson, L.
Author_Institution :
Telecommun. Res. Inst., Curtin Univ. of Technol., Perth, WA, Australia
fDate :
12/1/2000 12:00:00 AM
Abstract :
In this a paper, we introduce a modified tapped all-pass (MTA) structure for the sum of two all-pass functions. The new structure includes linear coefficients in the all-pass sections, allowing additional constraints such as null or group delay constraints for the filters. These null constraints are significant for applications when the suppression of the noise at certain frequencies is important. An alternative structure to incorporate the extra constraints is the modified tapped cascade (MTC) infinite impulse response structure. Design examples show that the MTA structure is less sensitive to quantization than the MTC structure in the passband. Moreover, the total number of multiplications is significantly reduced by using the MTA structure as compared to the MTC structure
Keywords :
Chebyshev filters; IIR filters; all-pass filters; cascade networks; digital filters; filtering theory; IIR filter approximation; additional specifications; all-pass functions; classical IIR filters; group delay constraints; linear coefficients; modified tapped all-pass structure; modified tapped cascade IIR structure; multiplications reduction; null constraints; quantization sensitivity; Band pass filters; Chebyshev approximation; Delay; Frequency; IIR filters; Nonlinear filters; Passband; Prototypes; Quantization; Transfer functions;
Journal_Title :
Circuits and Systems II: Analog and Digital Signal Processing, IEEE Transactions on
