Comparison of Highly Linear Resistive Mixers in Depletion and Enhancement Mode GaAs and GaN pHEMTs at Ka Band

In this paper, for the first time we develop and benchmark the performance of three down-converting Field Effect Transistor (FE T) resistive mixers at millimeter wave (mm W) frequencies employing $\pmb{0.15-\mu \mathrm{m}}$ enhancement (E)-mode Gallium Arsenide (GaAs) pseudomorphic high electron mobility transistors (pHEMTs), depletion (D)-mode GaAs pHEMTs, and D-mode Gallium Nitride (GaN) pHEMTs. Our experimental results at 27 GHz demonstrate that the E-mode mixer achieves the highest reported input 3rd order intercept point (IIP3) of 37.5dBm at mm W frequencies to the best of our knowledge. Also, operating at the same LO drive up to 20 dBm, the E-mode GaAs mixer impressively out performs both the D-mode GaAs and GaN mixers.