Passive mixer mismatch tuning using self-tests to suppress IM2
US8204467B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 10, 2009 |
| Grant date | Jun 19, 2012 |
| Priority date | — |
| Expiry date | Mar 30, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D2200/0086
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
The second-order inter-modulation distortion, originating in a differential passive mixer core from imbalance between devices, is reduced by compensating for the mismatch or load, by means of tuning the differential output impedance at the mixer core, or the input impedance of a filter coupled to the output of the passive mixer. Compensating for the imbalance allows greater suppression of even-order harmonics in the differential structure, which reduces second-order intermodulation at the output of the mixers. The compensation is achieved by tunable resistive elements that are calibrated by a built-in self-test architecture. The calibration circuit is deactivated during receiver operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.