HARMONIC TRAP FOR COMMON GATE AMPLIFIER

摘要

A circuit, a method and an apparatus, are described. A radio frequency (RF) signal received from a transmission line is provided to the source of a transistor in a common-gate amplification circuit. A series resonance connected to the source provides a low impedance path to ground for interfering RF components in the RF signal. The series resonance is tuned to provide a high impedance to a band of frequencies centered on a frequency of interest and to shunt interfering RF components outside the band of frequencies centered on the frequency of interest. The interfering RF components may include a harmonic of the frequency of interest.