Temperature and frequency variable gain attenuator
US7215219B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 15, 2005 |
| Grant date | May 8, 2007 |
| Priority date | — |
| Expiry date | Sep 23, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01P1/2135
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A temperature and frequency variable gain attenuator comprises a temperature variable attenuator and a temperature variable filter network whose resistances changed to c generate different responses that vary over temperature and frequency. At least three different thick film thermistors are used, with two of these used on the attenuator and a third one used on the filter network. The temperature coefficients of the thermistors are different and are selected so that the attenuator and filter network attenuation change at a controlled rate with changes in temperature while the impedance of the gain equalizer remains within acceptable levels. Substantially any temperature coefficient of resistance can be created for each resistor by properly selecting and mixing different inks when forming the thick film thermistors. Furthermore, the attenuator can have either a negative temperature coefficient of attenuation or a positive temperature coefficient of attenuation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.