Frequency synthesizer and frequency synthesizing method for converting frequency's spurious tones into noise
US9128536B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 2012 |
| Grant date | Sep 8, 2015 |
| Priority date | — |
| Expiry date | Mar 29, 2034 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F1/0328
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
One of the advantages of direct frequency synthesis technique (e.g., flying-adder architecture) is its capability of generating arbitrary frequency by utilizing the time-average-frequency concept. In the clock output of the direct frequency synthesizer, instead of one type of cycle, there are two types of cycles. Unlike the conventional one-type-cycle clock wherein clock energy is concentrated at its designed frequency, Time-Average-Frequency based clock spreads some of its energy into spurious tones, which could be harmful to certain applications. The spurious tones are caused by the periodic carry sequence generated from a fractional part accumulator inside the frequency synthesizer. The invention suggests a method and an apparatus to break this periodicity and convert the spurious tones into broadband noise.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.