Adaptive intermodulation distortion filter for zero-if receivers
US7706769B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 1, 2004 |
| Grant date | Apr 27, 2010 |
| Priority date | — |
| Expiry date | Jan 30, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/30
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A zero-IF receiver includes an adaptive filter that is enabled when intermodulation distortion is detected. The adaptive filter is configured as a notch filter that is centered at the location of the second-order intermodulation distortion, which, in a zero-IF receiver, is at zero Hertz. In a preferred embodiment, the frequency response of the high pass filter that is typically used in a conventional zero-IF receiver is adjusted when intermodulation distortion is detected. Preferably, the detection of the intermodulation distortion is based on one or more of the digital baseband signals, for ease of implementation, but analog processing may also be employed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.