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In this study, the authors present a 36:1 relative bandwidth active front‐end low‐noise amplifier (LNA) with power limiter that has been developed for airborne ultra‐wideband receiver systems. The proposed system is driven by an external antenna with a balanced mode with an input impedance of 150 Ω. The whole microwave monolithic integrated circuit (MMIC) embeds a protection from the presence of high‐level signals, an ultra‐wideband amplifier circuit, an active balun and an impedance transformer. It has a bandwidth ranging from 0.5 to 18.0 GHz with 14 dB gain, 4.5 dB noise figure (NF), 20 dB common‐mode rejection and 30 dBm input overload protection. The circuit has a single bias from the output port greatly simplifying its use within a receiving system and can be directly integrated into the antenna mechanical support. Test measurements are also provided.

Coronaviruses are a family of viruses that cause disease in mammals and birds. In humans, coronaviruses cause infections on the respiratory tract that can be fatal. These viruses can cause both mild illnesses such as the common cold and lethal illnesses such as SARS, MERS, and COVID-19. Air transmission represents the principal mode by which people become infected by SARS-CoV-2. To reduce the risks of air transmission of this powerful pathogen, we devised a method of inactivation based on the propagation of electromagnetic waves in the area to be sanitized. We optimized the conditions in a controlled laboratory environment mimicking a natural airborne virus transmission and consistently achieved a 90% (tenfold) reduction of infectivity after a short treatment using a Radio Frequency (RF) wave emission with a power level that is safe for people according to most regulatory agencies, including those in Europe, USA, and Japan. To the best of our knowledge, this is the first time that SARS-CoV-2 has been shown to be inactivated through RF wave emission under conditions compatible with the presence of human beings and animals. Additional in-depth studies are warranted to extend the results to other viruses and to explore the potential implementation of this technology in different environmental conditions.

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A Ka-Band, High Efficiency, Small Size Spatial Combiner (SPC) is proposed in this paper, which uses an innovatively matched quadruple Fin Lines to microstrip (FLuS) transitions. At the date of this paper and at the Author's best knowledge no such FLuS innovative transitions have been reported in literature before. These transitions are inserted into a WR28 waveguide T-junction, in order to allow the integration of 16 Monolithic Microwave Integrated Circuit (MMIC) Solid State Power Amplifiers (SSPA's). A computational electromagnetic model using the finite elements method has been implemented. A mean insertion loss of 2 dB is achieved with a return loss better the 10 dB in the 31-37 GHz bandwidth.