Demodulators – Amplitude modulation demodulator – Having specific distortion – noise or other interference...
Patent
1983-03-21
1985-09-17
LaRoche, Eugene R.
Demodulators
Amplitude modulation demodulator
Having specific distortion, noise or other interference...
329 50, H03D 300
Patent
active
045423474
ABSTRACT:
A demodulator circuit for demodulating a suppressed carrier phase modulated data input signal includes a carrier recovery circuit providing orthogonal reference carrier signals, first and second demodulation circuits for demodulating the signal with the orthogonal reference carrier signals, at least one data estimation circuit for deriving a first data estimation circuit from the demodulated signal, a second demodulated signal being delayed to obtain a signal which in combination with the first data estimation signal controls the carrier recovery circuit. The circuit further includes an automatic gain control which in response to the first data estimation and to a delayed first demodulated signal provides an AGC output signal. The AGC circuit is substantially unaffected by the noise in the input signal because of the matched filters circuit which is matched to the first demodulated signal and which in response thereto provides a filtered output signal having an optimum signal noise ratio at a predetermined instant of each data signal of the first demodulated signal, and a data sampling circuit for sampling the circuit output signal at predetermined instants to provide the first data estimation signal. A sweep generator circuit is operable to control a reference carrier signal in the modulation signal when the quality of a filtered output signal is not above a predetermined level.
REFERENCES:
patent: 4123718 (1978-10-01), Lampert et al.
patent: 4270221 (1981-05-01), Daniel
patent: 4377728 (1983-03-01), Hilbert
Breynaert Dirk
Verfaillie Guido A. M.
International Standard Electric Corporation
LaRoche Eugene R.
O'Halloran John T.
O'Hare Thomas P.
Pascal Robert J.
LandOfFree
Demodulator circuit with integrated automatic gain control does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Demodulator circuit with integrated automatic gain control, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Demodulator circuit with integrated automatic gain control will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-371849