Circuit arrangement for generating an IQ-signal
US7274922B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 20, 2004 |
| Grant date | Sep 25, 2007 |
| Priority date | — |
| Expiry date | Apr 14, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03H7/21
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
Circuits generate an IQ voltage or current signal having orthogonal I- and Q-parts of approximately equal amplitude from an electric input signal having a frequency varying slightly around a carrier frequency, without needing a complex mixer. The circuit includes at least one ohmic resistance and at least one reactance connected in series (for a voltage) or in parallel (for a current). The reactance has an impedance at the carrier frequency approximately matching the resistance value of the ohmic resistance. The I- and Q-parts of the voltage signal are tapped as voltage drops across the resistance and the reactance. With two such series circuit branches in parallel, both voltage signal parts can be referenced directly to a reference potential, e.g. ground. The I- and Q-parts of the current signal are tapped as currents flowing through the resistance and the reactance. The circuit can be integrated at the output of a bandpass filter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.