Arithmetic-free digital interpolation filter architecture
US5541864A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 26, 1994 |
| Grant date | Jul 30, 1996 |
| Priority date | — |
| Expiry date | Apr 26, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H17/0621
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A low precision Finite Impulse Response filter (FIR) is provided for filtering in a digital interpolation operation. The interpolation operation is comprised of two steps, a sampling rate conversion operation for interspersing zeroes between samples in an input sequence and a filtering step of filtering out images that result from this operation. The filtering operation utilizes a FIR filter that utilizes a low precision set of filter coefficients that are selected to tune the frequency response such that the low end frequency response including the pass band, the transition band, and the portion of the stop band immediately after the transition band provides a response equivalent to that commensurate with substantially higher precision FIR filter coefficients. A second, low pass filter section is provided for filtering the high frequency image energy at the output of the FIR filter to provide an overall filter response commensurate to that utilizing substantially higher precision FIR coefficients. The FIR filter coefficients utilized are restricted to the set of {-1, 0, +1} such that an arithmetic-free realization is provided wherein data is stored in a random access memory (68), …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.