The high power capabilities in combination with the low noise performance of Gallium Nitride (GaN) makes this technology an excellent choice for robust receivers. This paper presents the design and measured results of three different LNAs, which operate in C-, Ku-, and Ka-band. The designs are realized in 0.25 μm and 0.15 μm AlGaN/GaN microstrip technology. The measured noise figure is 1.2, 1.9 and 4.0 dB for the C-, Ku-, and Ka-frequency band respectively. The robustness of the LNAs have been tested by applying CW source power levels of 42 dBm, 42 dBm and 28 dBm for the C-band, Ku-band and Ka-band LNA respectively. No degradation in performance has been observed. I. INTRODUCTION Due to the current trends in the global security scenario the interest in secure and robust satellite communication systems is increasing. A space-born receiver is one of the most important, but also one of the most sensitive components in the satellite communication chain. These receivers must also be functional during severe jamming and no degradation is allowed due to high input powers from hostile electromagnetic attacks. Currently enabling technologies like GaN and SiC are being developed for both military as well as governmental and commercial applications. GaN is expected to improve the performance regarding robustness together with microwave capabilities comparable to currently used technologies like GaAs, InP and Si. Due to the combination of high power and low noise operation GaN is very suitable for the realization of secure robust RF front-end (RFFE) modules. In addition, the overdrive capability and survivability levels are exceptionally high. The development of both GaN HEMTs as well as MMIC processes makes it possible to realize GaN low noise receivers at millimeter wave frequencies. Such receivers are very attractive for secure communication systems due to the changing trade-off between performance and cost. Therefore GaN based receivers offer important potential for next generation satellite communication systems. This work aims at technology demonstrations at C-, Ku-and Ka-band by designing, building and testing GaN low noise