Ka-band low noise amplifiers based on InAlN/GaN technologies

Low noise amplifiers in receivers are usually addressed by III-V (narrow bandgap) technologies: but when the receivers are subject to EM exposure or jamming, the need for protection devices before the active low noise amplifier (LNA) degrades the overall noise figure, and decreases the effective radio link budget. This vulnerability of the LNA can be overcome thanks to robust designs or robust technologies. Nitride technologies are investigated for power modules in transmitters and stand as promising solutions to avoid the use of limiters for robust low noise circuits in receivers. This work focuses on HF noise in InAlN/GaN HEMT devices and circuits for Ka-band SATCOM applications. Different versions of LNA have been designed at 30 GHz, in hybrid and MMIC technologies. For these designs, 1-stage and 3-stages LNAs have been realized; 1-stage amplifiers are designed to assess and study the stress tolerance under RF signal, whereas 3-stages LNAs are designed as demonstrators of operational module for receiver's blocks (Gain>20dB featuring the lowest noise figure achievable).