Method and circuit for carrier control in a quadrature demodulator
US7978790B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 13, 2007 |
| Grant date | Jul 12, 2011 |
| Priority date | — |
| Expiry date | Dec 12, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D3/009
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The invention relates to a method and a circuit for carrier control in a quadrature demodulator, wherein a complex-value input signal (I, Q) is supplied to a mixer (1) to perform mixing with a mixing frequency (fm) to create a mixed signal (Ir, Qr), the mixed signal (Ir, Qr) is supplied to a processing section (s) to generate a processed signal (Ie, Qe), the processed signal (Ie, Qe) is supplied to phase measurement device (3) in order to measure a phase (φm) of the processed signal (Ie, Qe) and the measured phase (φm) is supplied to a phase controller (4) in order to control the mixing frequency (fm); wherein an idle time (z−d) is created at least during the processing in the processing section (2). To enable a fast switching-on transition, the mixing frequency (fm) is summed or integrated to create a mixing phase (φc), the mixing phase (φc) is used for the mixing operation, as well as fed back to the phase control (4, 23), and an error created by the feedback is compensated for with a time-delayed second feedback of the mixing phase (φc).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.