Parallel infinite impulse response (IIR) filter with low quantization effects and method therefor
US5432723A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 1993 |
| Grant date | Jul 11, 1995 |
| Priority date | — |
| Expiry date | Dec 2, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H17/0461
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A parallel IIR filter (100) has low quantization effects and includes a multiplier (103) which multiplies a digital input signal by a constant, and an arbitrary number of biquad filters (104, 105). Outputs of the multiplier (103) and each biquad filter (104, 105) are summed together in a summing device (106) to provide an output signal of the IIR filter (100). The IIR filter (100) first expresses its transfer function as a cascade form transfer function, and then calculates the constant as a product of a constant term of each cascade form biquad term. The IIR filter (100) partially decomposes the cascade form transfer function to provide first order terms, and calculates numerator coefficients of the first-order terms. Pairs of decomposed terms are recombined to provide a parallel form transfer function, from which parallel form coefficients are taken and applied to the biquad filters (104, 105).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.