New in-situ calibration of diode detectors used in six-port network analyzers

The authors present a novel method for calibrating the diode detectors used in six-port network analyzers without disconnecting the diodes. The method uses either a precision variable attenuator at the six-port input or a power meter connected to the six-port test port. No actual measurement of power is required to calibrate the diode detectors when an attenuator is used. The method is very well suited to in situ calibration of the diode detection circuits for the operation of the six-port with pulsed signals when the average power detected by the power meter drops to very low levels for low duty cycles. In these cases. The precision variable attenuator method is required.>