Method and apparatus for generating sliding tapered windows and sliding window transforms
US5373460A · kind A · utility
Inventor
Key dates
| Filing date | Mar 11, 1993 |
| Grant date | Dec 13, 1994 |
| Priority date | — |
| Expiry date | Mar 11, 2013 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG10L25/27
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for the computation of sliding windows and sliding window Fourier transforms and spectrograms requiring fewer operations in comparison with the current art. The sliding windows are realized using infinite impulse response filters. If the impulse response of one filter is equal to the impulse response of a second filter after a period of time, the impulse responses can be canceled thereby resulting in a composite filter with an impulse response of finite length. In certain realizations, the infinite impulse filters have identical components. These components can be combined into a single component in the composite filter thereby reducing the required number of computational operations. Sliding windows thus realized are employed in the generation of sliding window Fourier transforms and spectrograms. The windows can be modulated or unmodulated. For unmodulated windows, the signal to be processed is first multiplied by a discrete oscillator tuned to the desired frequency of the sliding window Fourier transform or spectrogram. Modulated windows are realized with infinite impulse filters containing high frequency components and therefore do not require use of osci…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.