Low Conversion Loss 188 GHz Doubler
The doubler is based on Indium Phosphide (InP) Double Heterojunction Bipolar Transistor (DHBT) process.
Motivation
The availability of fundamental tone sources in the millimeter-wave range is limited, which makes frequency multipliers an essential component in systems employing millimeter-wave signals.
Performance
The 188 GHz circuit utilizes a 1-finger DHBT having fT / fmax = 330 GHz / 420 GHz.
The minimum measured conversion loss is 0.7 dB at 180 GHz and 1.7 dB at 188 GHz with an output power of -3.4 dBm and -2.9 dBm correspondingly. The bias point is constant throughout the measurement with a collector voltage of 2.4 V. The collector current in saturation is approximately 10 mA.
Further increasing driving level a maximum output power of -1.1 dBm could be achieved at 188GHz.
At maximum drive the doubler demonstrates fairly constant output power in the entire frequency range from 150 GHz to 188 GHz.
The suppression of the fundamental frequency is better than 11 dB.
Further details
can be found in this .pdf: DOI: 10.1109/INMMIC.2017.7927292