Patent ID: 6882223

Claim:
Multi-band low noise amplifier comprising: a plurality of matching networks for receiving input signals from a plurality of frequency bands respectively; a plurality of differential pairs, bases of said plurality of differential pairs being coupled to outputs of said plurality of input matching networks, emitters and collectors of said plurality of differential pairs are connected together, respectively; a pair of common base transistors, emitters of said common base transistor pairs being coupled to collectors of said plurality of differential pairs; a first pair of inductors, one end of the inductor pairs being coupled to collectors of said common base transistor pair, the other end being coupled to a power supply; a pair of variable capacitors, one end of the variable capacitor pairs being coupled to collectors of said common base transistor pair, the other end being coupled to said power supply; a second pair of inductors, one end of said inductor pairs being coupled to emitters of said plurality of differential pairs, the other end of said inductor pairs being interlinked; and a current generator, one end of the current generator being coupled to a coupling point of said inductors, the other end of the current generator being coupled to ground.