Telecommunications – Transmitter – Amplitude modulation
Patent
1979-09-14
1980-12-02
Bookbinder, Marc E.
Telecommunications
Transmitter
Amplitude modulation
332 37D, 455116, 455126, H04B 102, H03C 106
Patent
active
042375550
ABSTRACT:
The feedback controlled modulation system comprises an extended range, gain controlled detector system disposed in a first feedback loop coupled between the output and input of an amplifier having a non-linear input-output characteristic; a gain controlled reference signal source coupled to the output of the detector system to provide a difference signal in the first feedback loop; and a gain controlling pulse generator coupled to the source and the detector system to simultaneously control the gain of the source and the gain of the detector system to control the shape of the difference signal so as to linearize the non-linear characteristic without loss of loop stability and without causing amplitude distortion in the first feedback loop. In addition, the modulation system includes an exciter which provides controllable amplitude, rectangular pulses; an amplitude modulator disposed in the first feedback loop coupled to the input of the amplifier and output of the exciter responsive to the rectangular pulses and an amplified version of the shaped difference signal; a second feedback loop coupled between the output and input of the exciter to provide an extremely flat top for each of the rectangular pulses; and a third feedback loop coupled to the first and second feedback loops responsive to a predetermined gated portion of the amplified version of the difference signal to produce a control signal for the second feedback loop to accurately control the amplitude of the flat top rectangular pulses so as to hold the amplitude of a baseline portion of the output signal of the modulator exactly at the threshold of the linearized characteristic.
REFERENCES:
patent: 3200336 (1965-08-01), Valakos et al.
patent: 3662290 (1972-05-01), Elliott
patent: 3668533 (1972-06-01), Fish et al.
patent: 4044308 (1977-08-01), Stites et al.
Bookbinder Marc E.
Hill Alfred C.
International Telephone and Telegraph Corporation
O'Halloran John T.
LandOfFree
Automatic modulation system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Automatic modulation system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic modulation system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2287762