Low-cost receiver using tracking bandpass filter and lowpass filter
US8145170B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 25, 2008 |
| Grant date | Mar 27, 2012 |
| Priority date | — |
| Expiry date | Dec 13, 2030 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/4446
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A receiver (400) includes a tracking bandpass filter (420), a tunable lowpass filter (434), a local oscillator (442), and a mixer (444). The tracking bandpass filter (420) has an input for receiving a radio frequency (RF) input signal, and an output. The tunable lowpass filter (434) has an input coupled to the output of the tracking bandpass filter (420), and an output. The local oscillator (422) has a first output for providing a local oscillator signal, which is characterized as being a square wave signal at the desired intermediate frequency (IF). The mixer (444) has a first input coupled to the output of the tunable lowpass filter (434), a second input coupled to the output of the local oscillator (442), and a first output for providing an IF signal at the desired IF. The tunable lowpass filter (434) is configured to substantially attenuate a third harmonic of the frequency of the local oscillator signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.