A GaN-on-Si MMIC LNA for Spaceborne Cloud Profiling Radars and <i>W</i>-Band Telecom Links

The European Space Agency (ESA) has designed a 70–95 GHz gallium-nitride-on-silicon (GaN-on-Si) monolithic microwave integrated circuit (MMIC) low noise amplifier (LNA) for future spaceborne cloud profiling radar (CPR) instruments at 94 GHz, like Wivern. The MMIC LNA has also been designed to be compatible with the W-band telecommunication feeder down (71–76 GHz) and up-links (81–86 GHz). The MMIC test results show an average noise figure of 3.9 dB and an average gain of 22.5 dB. The minimum measured noise figure is 2.8 dB at 77 GHz. The MMIC was subject to an input overdrive test and survived the application of a pulsed CPR representative signal with a level of +23 dBm without showing any subsequent malfunction. To the best knowledge of the authors, these results show: 1) the best overall performance for any GaN-on-Si LNA reported to date in the 70–95 GHz range and 2) the first reporting in the open literature of an input overdrive test in a W-band GaN LNA.