Adaptive power control circuit

DETAILED DESCRIPTION Accordingly, it is an object of this invention to provide an adaptive power control circuit for a transmitter amplifier which provides slow speed response for constant power conditions and high speed response for desired abrupt power changes.
It is a further object of this invention to provide an adaptive power control circuit for a transmitter amplifer which is particularly adapted for mobile operation in a trunked communication system.
In practicing the invention, a protection circuit is provided for controlling a transmitter amplifer which produces an RF output varying in response to a control signal applied thereto.
The power control circuit includes sensing means coupled to the transmitter amplifier, for sensing RF power and for generating a power signal representative of RF power.
A signal processing circuit is coupled to the sensing means for filtering the power signal such that wide bandwidth filtering is utilized in response to a desired change in transmitter amplifier power, for a period of time sufficient to permit the change in transmitter amplifier power and such that narrow bandwidth filtering is otherwise utilized.
In addition, a comparator is coupled to the signal processing circuit, for generating a control signal which varies in accordance with the difference between a reference voltage and filtered power signal.
The comparator is coupled to the transmitter amplifier for applying the control signal to the transmitter amplifer to vary the RF power developed by the transmitter.