Krause, SvenSvenKrauseMichler, FabianFabianMichlerKölpin, AlexanderAlexanderKölpinRudolph, M.M.RudolphHeinrich, WolfgangWolfgangHeinrich2021-06-112021-06-112021-08IEEE Microwave and Wireless Components Letters 31 (8): (2021-08)http://hdl.handle.net/11420/9728In this paper, we demonstrate a digital correction method for extending the dynamic range of a six-port radar system based on detector diodes. An individual diode gain is considered to depend on output voltage, which can be approximated as a linear function in order to extrapolate the diode’s square-law response to higher input powers. The individual diode coefficients are extracted during an initial calibration measurement utilizing the interferometric working principle. A six-port junction in combination with power detectors based on Si Schottky diodes operating at 24 GHz has been employed to validate the concept. Reduction of the 3rd- and 5th- order harmonic of up to 35 dB and 22 dB, respectively, have been achieved at the highest input power of 8 dBm. The correction was applied for a wide range of operating conditions. As a result, the increase of phase error under large-signal and high power operation is effectively compensated and remains as low as under small-signal conditions. Thus, phase accuracy is maintained beyond the classical dynamic range of detector diodes in six-port applications so far.en1531-1309202189971000Calibrationcalibration techniqueDetectorsdigital correctiondisplacement measurementHarmonic analysisRadio frequencyRF signalsSchottky diodesSix-port radarVoltage measurementJournal Article10.1109/LMWC.2021.3084338Other