PROCESS AND SYSTEM FOR ADJUSTING THE LEVEL OF THE SPURIOUS LINES OF THE OUTPUT FREQUENCY SPECTRUM OF A SINGLE-SIDEBAND FREQUENCY TRANSPOSITION DEVICE, IN PARTICULAR INCORPORATED INTO A MOBILE TELEPHONE
US6393258B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 20, 1999 |
| Grant date | May 21, 2002 |
| Priority date | — |
| Expiry date | Oct 20, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D7/18
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A process for adjusting a level of spurious signal spectral lines in an output frequency spectrum provided by a single-sideband frequency mixer includes the step of generating two mutually phase-shifted test signals defined by a plurality of parameters, and applying the two test signals to respective first and second inputs of the single-sideband frequency mixer. The level of each of the spurious signal spectral lines are measured for different test values corresponding to the plurality of parameters of the two test signals. Reference values are determined for the plurality of parameters for minimizing the level of the spurious signal spectral lines. The reference values are determined by a numerical calculation performed on a predetermined number of different test values of the plurality of parameters, and corresponding measured values of the levels with respect to two parabolic relations linking the levels of the two spurious signal spectral lines with the plurality of parameters. This process minimizes a duration of the adjustment by using a reduced number of test values.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.