Low power high dynamic range active mixer based microwave downconverter with high isolation

Abstract

A down converter, including first and second biasing circuits, mixer, and transformer coupled to receive amplifier output signal. The first and second biasing circuits each include a biasing transistor and a first and second node, respectively. Mixer includes first and second transistors coupled to first node and third and fourth transistors coupled to second node. The second and fourth transistors are coupled to a third node. The first and third transistors are coupled to a fourth node. Mixer also includes a first resistor coupled to the fourth node and a supply voltage node and a second resistor coupled to the third node and a supply voltage node. Transformer includes a primary winding coupled to receive the amplifier output signal and to a supply voltage and a secondary winding coupled to mixer and first biasing circuit at first node and coupled to mixer and second biasing circuit at second node.