Frequency selective isolation circuit and method for suppressing parametric oscillation

摘要

In a system comprising a plurality of gain elements configured in parallel to one another, a harmonically tuned filter provides an isolation circuit to prevent odd-mode differential oscillations. A harmonically tuned filter comprises resistors, inductors, and capacitors (RLC) to selectively allow one or more specific harmonics to pass through the isolation circuit to suppress the odd-mode oscillation. Direct current (DC) and other non-harmonically-related frequencies do not pass through the isolation circuit. Since the resistor is used to dissipate specifically the energy of the harmonic frequencies causing the odd-mode oscillation, the current density through the resistor is much lower than the current density of a typical odd-mode resistor without a harmonically tuned filter.