METHOD AND DEVICE FOR PROTECTING A HIGH-FREQUENCY POWER AMPLIFIER AGAINST A TERMINATION FAULT

摘要

A mismatch protection circuit for high frequency power amplifiers includes a waveguide coupler connected to the output of the high frequency power amplifier. The waveguide coupler includes a first detector diode, which supplies, according to the power level being applied, a first voltage, which corresponds to the effective power that is fed in. The waveguide coupler also includes a second detector diode, the outputted second voltage of which corresponds to the power that is reflected due to the mismatch. The protection circuit further includes a control circuit, with which the amount of a mismatch is determined from the difference between the voltage value at the second diode and a reference voltage. The output stage(s) of the high frequency power amplifier(s) is and/or are switched on or off, depending on whether the voltage difference drops below or exceeds a given reference value.