Circuit configuration for direct modulation
US6983131B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 7, 2002 |
| Grant date | Jan 3, 2006 |
| Priority date | — |
| Expiry date | Sep 1, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D7/166
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A circuit configuration for direction modulation contains an oscillator, whose output signal is split into quadrature components for modulation with a useful signal. A frequency shifting circuit has the effect that that the output frequency and the frequency of the oscillator are fractional rational multiples with respect to one another. The circuit contains a phase shifter for generating first further quadrature components and also a divider for generating second further quadrature components. The quadrature components are mixed with one another. As a result of the frequency offset, the oscillation frequency of the oscillator is shifted to outside the useful frequency band. Remodulation effects do not influence the adjacent channels. The circuit can be realized simply and cost-effectively and, in particular, requires only one oscillator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.