Noise current feedforward for noise cancellation in the wideband transformer shunt feedback low noise amplifier

Abstract

A noise current feedforward (NCF) technique for noise cancellation in the wideband transformer shunt feedback (TSF) low noise amplifier (LNA) is proposed. The NCF can detect and cancel the thermal noise of the TSF network. It is also suitable to cancel those noise contributed by the passive unilateral shunt feedback networks in common current mode LNAs. Implemented in SMIC 0.18 [mu]m CMOS process and operated in the typical radio astronomy frequency range from 0.6 GHz to 1.6 GHz, the TSF LNA that employs the NCF shows approximately 0.2-0.5 dB lower noise figure than the overwhelming resistive shunt feedback LNA that exploits a conventional noise voltage feedforward technique when consuming the same power.[PUBLICATION ABSTRACT]