Circuit arrangement for generating signals with different phases
US5949267A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 7, 1997 |
| Grant date | Sep 7, 1999 |
| Priority date | — |
| Expiry date | Oct 7, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H11/22
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
The invention relates to a circuit arrangement for generating two signals having a phase difference of approximately 90 degrees. The invention is preferably applied in the demodulator of a radio receiver. In order to shift the phase of a signal one idea of the invention is to use a distributed resistance/capacitance circuit or a distributed RC circuit (Z.sub.10, Z.sub.20) in connection with a signal amplifying means (A.sub.1, A.sub.2). The operation of the circuit is not frequency dependent and a circuit adjustment is not necessarily required in order to calibrate the phase difference, because the distributed RC circuit can provide an substantially constant phase shift of .+-.45 degrees over a wide frequency range. The whole circuit can be integrated into one component, because a distributed RC circuit is easily made on the same integrated circuit substrate as the amplifying means, and thus the circuits can be made into a small size and at low manufacturing costs.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.