A 2GHz-band SiGe HBT low noise amplifier (LNA) achieving high saturation power and low distortion performance is described. It has a novel diode / resistor dual bias feed circuit for the base of the HBT to extend its PldB.In small signal region, the conventional resistor feed circuit is a dominant base current source, but in large signal region, the diode turns on and the diode feed circuit can supply base current like a voltage source which allows higher output power and linearity. The fabricated dual feed type LNA shows the PldB improvement of 5dB compared with the conventional resistor feed LNA.

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