High-frequency analysis of linearity improvement technique of common-emitter transconductance stage using a low-frequency-trap network

It is well known that a low-frequency-trap network can be added to the base of an inductively-degenerated common-emitter transconductance stage to improve its third-order intercept point, but not its 1-dB compression point. High-frequency equations in Volterra series are used to explain this phenomenon. Analytical and experimental results show that the third-order intercept point increases with the capacitance within the low-frequency-trap network.