Abstract: A subharmonic carrier-canceling baseband/K upconverter system uses a first splitter to separate an incoming RF signal into two equal components: in-phase (1) and quadrature (Q, 180 degrees delayed). A second splitter is used to separate a local oscillator signal into two equal components: in-phase (I) and quadrature (Q, 90 degrees delayed). A first subharmonic mixer is used to mix both I components, while a second subharmonic mixer is used to mix both Q components. The outputs of both mixers are then combined to produce an output RF signal having reduced second order harmonics close to said local oscillator frequency.

Abstract: A cascode low noise amplifier has high linearity while maintaining desirable values of other cascode configured low noise amplifier parameters. Emitter degeneration is employed to improve IIP3 while maintaining gain through bias optimization and providing a termination for harmonics produced in the circuit, resulting in maximization of linearity and dynamic range providing good noise figure, gain, in/out isolation and return loss.