Patent ID: 11863131
Assignee: nan
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 13:
14. An amplifier comprising:
a negative resistance network comprising a network characterized by a negative ratio of a voltage between output terminals of the negative resistance network and to a current flowing into the output terminals of the negative resistance network over a frequency band including F0;
a reactance network whose resonant frequency is configured to be varied by means of a DC voltage;
a bias network configured to present the DC voltage to the reactance network to vary the resonant frequency; and
a circulator comprising at least three ports, wherein:
the at least three ports including an input port, an output port, and a control port,
a signal at an input port of the circulator will be amplified at an output port of the circulator over a very narrow band of frequencies centered at F0, and
the amplifier is configured to vary F0 by varying the voltage supplied by the bias network while a gain of the amplifier remains constant without adjusting the value of the negative resistance or any other bias.