Telecommunications – Receiver or analog modulated signal frequency converter – Frequency or phase modulation
Patent
1989-09-29
1990-10-23
Eisenzopf, Reinhard J.
Telecommunications
Receiver or analog modulated signal frequency converter
Frequency or phase modulation
455214, 455325, 455339, 455340, H04B 130
Patent
active
049658530
ABSTRACT:
A zero-IF radio receiver circuit comprises an input filter (3), quadrature mixers (9,10), d.c.-blocking capacitors (24,26) and a demodulator (22). The circuit is partly integrated on a semiconductor chip and an inductive component of the input filter comprises one or more of the chip bond-wires. In order to compensate for the inevitable variation of the inductance of these bond-wires from circuit to circuit part of the signal from the local oscillator (12) is added to the input signal before its application to the input filter and the d.c. component of the resulting output from one mixer (10), which component is representative of the phase shift of the local oscillator signal produced by the input filter and hence of any tuning error of this filter, is applied to a tuning control input (30) of the filter to reduce the error. Alternatively the tuning control signal may be adjusted to maximize the sum of the squares of the d.c. components of the signals in the two IF channels and hence minimize the attenuation produced by the input filter.
REFERENCES:
patent: 4408350 (1983-10-01), Donath
patent: 4476583 (1984-10-01), Muterspaugh
patent: 4653117 (1987-03-01), Heck
patent: 4718113 (1988-01-01), Rother et al.
patent: 4731877 (1988-03-01), Moon
patent: 4776039 (1988-10-01), Kkaiwa
Charouel Lisa
Eisenzopf Reinhard J.
Lobato Emmanuel J.
U.S. Philips Corp.
LandOfFree
Radio receiver circuit with tuning feedback control for a tunabl does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Radio receiver circuit with tuning feedback control for a tunabl, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radio receiver circuit with tuning feedback control for a tunabl will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-772631