Telecommunications – Receiver or analog modulated signal frequency converter – Frequency or phase modulation
Patent
1989-11-02
1991-03-26
Eisenzopf, Reinhard J.
Telecommunications
Receiver or analog modulated signal frequency converter
Frequency or phase modulation
455316, 455324, 375 77, H04B 130
Patent
active
050036211
ABSTRACT:
A direct conversion FM receiver that comprises a quadrature mixer, an A to D converter, a digital demodulator, a digital phase lock loop, and frequency offset setting means is disclosed. The quadrature mixer receives FM signals and mixes them with a local oscillator signal to produce an analog in-phase baseband signal and an analog quadrature baseband signal. The analog in-phase baseband signal and the analog quadrature baseband signal are converted into digital signals by the A to D converter. The digitally converted baseband and quadrature signals are digitally demodulated and filtered by the digital demodulator such that modulation information is produced. The modulation information is used, at least in part, to control the phase lock loop means. In addition, the phase lock loop is offset by the frequency offsetting means such that the desensing components of the analog devices are minimized, thus, substantially reducing the need for tight component tolerance of DC sensing components and the need for manufacturing adjustments of DC desensing components.
REFERENCES:
patent: 4464770 (1984-08-01), Maurer et al.
patent: 4639682 (1987-01-01), Takeuchi
patent: 4653117 (1987-03-01), Heck
patent: 4677690 (1987-06-01), Reed
patent: 4733403 (1988-03-01), Simone
patent: 4750214 (1988-06-01), Hart et al.
patent: 4803700 (1989-02-01), Dewey et al.
patent: 4817167 (1989-03-01), Gassmann
patent: 4837853 (1989-06-01), Heck
patent: 4852123 (1989-07-01), Bickley
patent: 4857928 (1989-08-01), Gailus et al.
Charouel Lisa D.
Eisenzopf Reinhard J.
Krause Joseph P.
Markison Timothy W.
Motorola Inc.
LandOfFree
Direct conversion FM receiver does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Direct conversion FM receiver, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Direct conversion FM receiver will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-623849