In the article, we have proposed to use microwave-fluctuation meters resistant to external intense electromagnetic noise in order to measure the low-frequency (LF) noise of microwave transistors working under these conditions. The transistor located on the board is excited by a low-noise microwave generator, the oscillation amplitude of which, being modulated by the LF noise of the transistor, is measured by a microwave spectrum analyzer. The proposed method was tested on GaN/AlGaN heterotransistors, in whose channels the electron density was formed by spontaneous and piezoelectric polarization. In addition to experimental testing, a theoretical justification for the method is presented. We obtained conditions in which the normalized spectra of oscillation amplitude fluctuations were similar to the normalized LF noise of the transistor current.

Impact peril for warm-blooded organisms produced via sequence by ultra-wideband electromagnetic sub-nanosecond pulses, used in various scientific and technological applications, is assessed by radiophysics and classic mechanics calculated methods. Threshold values of the sequence parameters whose excess for a long time can become perilous for human have been determined. Keywords: ultrashort electromagnetic pulse (USEMP), electromagnetic impact, warm-blooded organism, free and bound charges.

Impact peril for warm-blooded organisms produced via sequence by ultra-wideband electromagnetic sub-nanosecond pulses, used in various scientific and technological applications, is assessed by radiophysics and classic mechanics calculated methods. Threshold values of the sequence parameters whose excess for a long time can become perilous for human have been determined.

Mechanisms of reversible and irreversible failures that occur in microwave semiconductor devices, microcircuits, and microprocessors under the impact of powerful electromagnetic pulses, either single or periodic, are analyzed. It is shown that, in microprocessors, failures of both types are generated by the electrothermal instabilities, being developed within negligibly small volumes of a device. The dependences of the threshold energy of failures on the pulse amplitude, duration, and repetition rate are explained. The results of the calculation are consistent with the experimental data.

We solve the problem of determination of the conditions under which the source of microwave pulses and the source of ultra-wideband electromagnetic pulses have an identical resulting impact in terms of energy on semiconductor elements of technical means without special receiving antennas. It is shown that sources of microwave pulses, whose carrier frequencies range from hundreds of megahertz to several gigahertz, reach the desired effect at lower energy costs. However, as the carrier frequency increases, their energy efficiency becomes lower, and ultra-wideband sources turn out to be more efficient in many practical cases.

In this paper, we solve the problem of dissipation of the energy of electromagnetic radiation in semiconductor devices of technical means, in which the fields are captured not by directional frequency-selective antennas, but by multidirectional receptors. The impact of both narrow-band microwave pulses with various carrier frequencies and ultrashort electromagnetic pulses, the spectrum of which extends to frequencies on the order of several GHz, is considered. The calculation results agree with the published experimental data.

It has been proved by computer simulation methods that for given antenna parameters, three parts of energy of ultrashort electromagnetic pulses, namely, energies emitted to the far zone, perceived by the receptor load, and reflected back from the antenna to the oscillator, significantly and differently depend on the duration of the leading and trailing edges of the excitation pulse. The technique proposed in the paper permits finding tradeoff solutions in the design of energetically efficient radiators intended for testing technical equipment for immunity to electromagnetic impacts.

AbstractIt is established experimentally that noticeable changes in the I – V characteristics and low-frequency noise in 4 H -SiC pin diodes irradiated by electrons with an energy of 0.9 MeV are observed after doses of Φ ≥ 1.4 × 10^15 cm^–2. The currents in the forward and reverse branches of the I – V characteristics vary nonmonotonically at voltages lower than 2 V with increasing dose, which is explained by the interaction between the excited electronic subsystem and metastable defects. In this case, a steady increase in the ideality factor and the series resistance of diodes in the region of exponential growth of the I – V characteristics at voltages exceeding 2 V is observed. The reliable operation of microwave devices with low-noise 4 H -SiC pin diodes under conditions of electron irradiation is possible up to a cumulative dose of Φ ≤ 10^15 cm^–2. In microwave devices, the level of low-frequency noise in which is irrelevant but the stabile regime of parameters is of importance, the dose can be increased to Φ ≈ 8 × 10^15 cm^–2.

It is established experimentally that noticeable changes in the I–V characteristics and low-frequency noise in 4H-SiC pin diodes irradiated by electrons with an energy of 0.9 MeV are observed after doses of Φ ≥ 1.4 × 1015 cm–2. The currents in the forward and reverse branches of the I–V characteristics vary nonmonotonically at voltages lower than 2 V with increasing dose, which is explained by the interaction between the excited electronic subsystem and metastable defects. In this case, a steady increase in the ideality factor and the series resistance of diodes in the region of exponential growth of the I–V characteristics at voltages exceeding 2 V is observed. The reliable operation of microwave devices with low-noise 4H-SiC pin diodes under conditions of electron irradiation is possible up to a cumulative dose of Φ ≤ 1015 cm–2. In microwave devices, the level of low-frequency noise in which is irrelevant but the stabile regime of parameters is of importance, the dose can be increased to Φ ≈ 8 × 1015 cm–2.

It is demonstrated that a number of relatively thin electric pulses that cause the catastrophic failure of a transistor due to the accumulation of defects exponentially increases with decreasing pulse energy when the pulse energy is less than the burnout energy by a factor of no less than two. A stronger alternative destruction effect is implemented if the energy is comparable with the burnout energy.

A numerical model, as well as a simpler analytical one, which describe heat accumulation in microwave semiconductor devices exposed to high-power electric-pulse trains, are constructed. Conditions are estabtished under which heat is accumulated with each subsequent pulse up to the onset of a catastrophic failure caused by the device burnout. It demonstrated that short-pulse trains with a small pulse period-topulse duration ratio are most dangerous.

It is shown that to use the maximum share of the energy of a unipolar ultrashort electric pulse, its duration and shape, as well as the transmitting antenna parameters should, be related to the receiver center frequency and passband in a certain manner. Distortions introduced by the propagation effects to the received-radiation spectrum shape increase with broadening radiation and receiver frequency bands.

The principle of integral Lagrangian minimization is used to explain the basic phenomena taking place in a vortex tube: separation of gas molecules in energy, tendency for an increase in the Mach number, and gas temperature nonadiabatic radial distribution. Reasons for turbulence are discussed.

The irreversible equations of thermodynamic transport phenomena are changed to tent mapping. It is shown that a tent map may serve as a model of an open system capable of self-organization and evolution.

The energy and dynamic characteristics of self-organizing and organized physical systems in which particles interact via electric fields are consistently considered in terms of the integral Lagrangian minimization. It is shown that the energy dissipation plays a minor role in self-organization processes. Two types of work are distinguished, basic differences and similarities between the systems are revealed, and comparison with living organisms is made.

The conditions for the energy equivalence of the effect of high-power microwave pulses and electrical video pulses on semiconductor devices are formulated and experimentally tested. The application of the video-pulse method is validated for the determination of parameters that characterize the hardness of micro-wave semiconductor devices against high-intensity electromagnetic interference capable of causing catastrophic failure.