Method and apparatus for improved direct digital frequency synthesizer
US7539716B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 26, 2005 |
| Grant date | May 26, 2009 |
| Priority date | — |
| Expiry date | Feb 24, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F1/0342
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An improved DDFS includes a minority-bit detector to permit a series of cascaded transformation stages to perform half or less than half of the rotational operations otherwise required by detecting whether the required rotation or non-rotation operations are in the minority and performing only the operations in the minority. This substantially reduces the number of minority-select butterfly stages that would otherwise be required. The cascaded transformation stages include a preliminary set of lookup tables in ROM memory, one of which is selected in accordance with the minority-bit detector and may include a subsequent set of butterfly stages providing the inputs to the minority-select butterfly stages.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.