In recent years, there has been increased interest in the terahertz waveband for application to ultra-high-speed wireless communications and remote sensing systems. However, atmospheric propagation at these wavelengths has a significant effect on the operational stability of systems using the terahertz waveband, so elucidating the effects of rain on propagation is a topic of high interest. We demonstrate various methods for calculating attenuation due to rain and evaluate these methods through comparison with calculated and experimental values. We find that in the 90 -225 GHz microwave band, values calculated according to Mie scattering theory using the Best and P-S sleet raindrop size distributions best agree with experimental values. At 313 and 355 GHz terahertz-waveband frequencies, values calculated according to Mie scattering theory using the Weibull distribution and a prediction model following ITU-R recommendations best agree with experimental values. We furthermore find that attenuation due to rain increases in proportion to frequency for microwave-band frequencies below approximately 50 GHz, but that there is a peak at around 100 GHz, above which the degree of attenuation remains steady or decreases. Rain-induced attenuation increases in proportion to the rainfall intensity.

Electromagnetic-fault injection (EM-FI) setups are appealing since they can be made at a low cost, achieve relatively high spatial resolutions, and avoid the need of tampering with the PCB or packaging of the target. In this paper we first sketch the importance of understanding the pulse characteristics of a pulse injection setup in order to successfully mount an attack. We then look into the different components that make up an EM-pulse setup and demonstrate their impact on the pulse shape. The different components are then assembled to form an EM-pulse injection setup. The effectiveness of the setup and how different design decisions impact the outcome of a fault injection campaign are demonstrated on a 32-bit ARM microcontroller.

We investigate the effects of EM pulses on an ATmega328p 8-bit microcontroller. We establish which areas of the chip are sensitive to EM pulse injection and describe the fault model for these sensitive areas. Furthermore, we compare our results to those of a previous study, which examined the effects of laser fault injection on the same device.

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