HFET Resistive Mixers for Frequencies above 100 GHz

The 4th International Symposium on Space Terahertz Technology

Herbert Zirath*, ilcho Angelov*, Niklas Rorsrnan*, Christer Karlsson*, RobertM. Weikle,II** and Erik L. Kollberg*

Others  :  http://www.nrao.edu/meetings/isstt/papers/1993/1993123000.pdf
PID  :  28461

来源: CEUR

【 摘 要 】

The development of HFETs based on InGaAs alloys has, during the last few years, pushed the frequency limit of semiconductor based amplifiers up to several hundred GHz. So far, however, mixers are usually based on either Schottky barrier diodes or SIS-diodes. In future receiver applications it would be suitable to integrate the amplifier, mixer, and even the oscillator on the same chip. For this purpose, we have investigated two different types of resistive mixers, a fundamentally pumped mixer where the LO is applied to the gate,modulating the source-drain resistance, and a subharrnonically pumped resistive mixer, based on two similar HFETs in parallel, pumped at each gate with the same LO-amplitude but 1800 out of phase. The pumping frequency is halved compared to the fundamentally pumped case since the combined source-drain conductance waveform varies with twice the LO-frequency. This feature is very attractive a high frequencies where it is difficult to obtain high powers.The resistive FET mixer is also attractive from the intemiodulation distortion point of view.