Amplifiers – Hum or noise or distortion bucking introduced into signal...
Patent
1993-02-10
1995-01-10
Pascal, Robert J.
Amplifiers
Hum or noise or distortion bucking introduced into signal...
330284, H03F 132
Patent
active
053811100
ABSTRACT:
Spurious frequencies are suppressed in a transmitter by an RF pulse fall time controller circuit comprising a quadrature hybrid matched attenuator located between a predriver and the first stage of class "C" driver amplifiers. The circuit linearly attenuates RF pulses and slows pulse fall time. Operation of the circuit is initiated when the rising edge of a pretrigger starts a pretrigger generator which then triggers the application of current bias to the attenuator circuit. After a controlled period of time, the circuit decreases the forward current bias of PIN diodes in the attenuator thereby increasing the diodes' series resistance and increasing the attenuation of the RF pulses. This creates a slow pulse fall time thereby suppressing spurious emissions caused by parasitic ringing of the cascaded Class C common base transistor amplifiers in the transmitter.
REFERENCES:
patent: 4320399 (1992-03-01), Buck et al.
patent: 4379996 (1983-04-01), Weber
patent: 4588958 (1986-05-01), Katz et al.
patent: 4928072 (1990-05-01), Scott
Drake Peter R.
Merrill, deceased Philip R.
O'Leary Thomas M.
Dawson Walter F.
Dinh Tan
Pascal Robert J.
Raytheon Company
LandOfFree
Spurious frequency suppressor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Spurious frequency suppressor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Spurious frequency suppressor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-853703