Variable-gain low noise amplifier for digital terrestrial applications
US7634244B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 2005 |
| Grant date | Dec 15, 2009 |
| Priority date | — |
| Expiry date | Sep 15, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/52
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A multi-stage amplifier assembly configured to receive a terrestrial digital television (“DTV”) input signal including multiple frequency channels. The amplifier assembly optionally includes a PIN diode coupled across differential inputs to a first stage of the multi-stage amplifier assembly. The PIN diode is controlled to attenuate the input when an exceptionally large signal is present in a channel adjacent to a desired channel. The PIN diode, essentially a variable resistor, permits the multi-stage amplifier assembly to maintain dynamic range in such situations for reasonable tradeoffs. The amplifier assembly further optionally includes an out-of-band second stage LNA. The amplifier assembly further optionally includes a multi-band input filter. The multi-band filer insures that the AGC operates on the TV band of interest, thus improving the linearity of the system. The invention can be implemented in CMOS and/or SiGe.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.