Anti-demodulator circuit, filtering device and demodulator...

Telecommunications – Transmitter and receiver at separate stations – Plural transmitters or receivers

Reexamination Certificate

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

C455S213000, C455S214000, C455S293000, C455S302000, C455S306000, C455S339000, C455S309000, C375S323000, C375S324000, C375S340000

Reexamination Certificate

active

06937871

ABSTRACT:
The invention relates to an anti-demodulator circuit which is fundamentally built up in the same way as a demodulator circuit but, instead of a bandpass filter as generally used in a demodulator, comprises a notch filter which receives an input signal comprising a useful signal and an interference signal, and generates a filtered signal. The notch filter has a center frequency which approximately corresponds to the frequency of the input signal so as to suppress at least a part of the useful signal. The anti-demodulator circuit further comprises a mixer circuit which receives the filtered signal and a phase-shifted input signal and supplies a demodulated output signal which substantially corresponds to the interference signal.The invention can be particularly used in connection with a filtering device for suppressing interference signals based on adjacent channel disturbances in FM radios, in which the bandwidth of the filtering device is controlled in dependence upon the output signal of the anti-demodulator circuit.

REFERENCES:
patent: 4866779 (1989-09-01), Kennedy et al.
patent: 5307517 (1994-04-01), Rich
patent: 5357574 (1994-10-01), Whitecar
patent: 5519890 (1996-05-01), Pinckley
patent: 5613234 (1997-03-01), Vella-Coleiro
patent: 6714776 (2004-03-01), Birleson
patent: 6807405 (2004-10-01), Jagger et al.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Anti-demodulator circuit, filtering device and demodulator... does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Anti-demodulator circuit, filtering device and demodulator..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Anti-demodulator circuit, filtering device and demodulator... will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-3441060

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.