Wideband IF image rejecting receiver
US6636730B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 23, 1998 |
| Grant date | Oct 21, 2003 |
| Priority date | — |
| Expiry date | Dec 23, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D3/007
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A system and method for effecting wideband image rejection. In a receiver implementation, the inventive method includes the steps of receiving a first signal in a first frequency band and generating in-phase and quadrature signals therefrom. The phase of the in-phase signal is shifted to provide a second signal and the phase of the quadrature signal is shifted to provide a third signal. A predetermined phase relationship is thereby effected between the second and the third signals. The second and third signals are then summed to provide an output signal which has minimal interference from a mixing signal. In an illustrative receiver application, the phase shifting is achieved via the use of all pass networks. Each of the all pass networks include a differential amplifier having first and second input terminals. The first and the second terminals are connected to a first end of first and second resistive elements, respectively. The second ends of the first and second resistive elements are connected to a common input terminal for the network. The first input terminal is a negative terminal and is connected to an output terminal of the network. The second terminal is a positive termi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.