Vol 61, No 11 (2016)

A method for solving the problem of transmission of symmetric Е- and Н-waves of a circular waveguide with perfectly conducting walls through an azimuthally symmetric diaphragm of a bianisotropically gyrotropic material is developed. Solving the problem is reduced to the numerical solution of a system of partial differential equations for the potentials. Conditions for the mutual transformation of the Н₀₁- and Е₀₁-waves passing through ferrite and plasma diaphragms in a longitudinal magnetic field are studied numerically.

By the example of a range-sum three-position active radar system with cooperative reception, a procedure for calculation of the accuracy of measuring the target coordinates that is based on inversion of the multidimensional Fisher information matrix is presented. The set of primary measurement errors in bistatic delays (ranges), which are determined by the action of the noise of the receivers, atmospheric fluctuations of the propagation delay, and uncertainties of the positions topo binding of the multistatic radar system, is taken into account. An example of calculation of the root-mean-square deviations of the errors of the three-coordinate measurement is given.

The problem concerned with lighting of objects and surfaces by means of artificial incoherent microwave sources is considered with the aim of their subsequent observation with the help of radiometric equipment. Transmitters based on dynamic chaos generators are used as wideband incoherent microwave emission devices. The experimental sample of the given device, namely, radio light lamp based on the chaos microgenerator, and its characteristics are described.

A method of equivalent currents and energy method allow significant simplification of the calculation of acousto-electronic devices in comparison with alternative methods based on the normal Auld modes, Shockley–Ramo theorem, reciprocity principle, and Green function. A common character of four original models of piezoelectric and magnetostriction currents that serve as sources of electromagnetic perturbations is demonstrated and proven.

The following-wave amplification mode of a model of the clinotron with linear electron trajectories is studied in the framework of linear and nonlinear theories. It is demonstrated that the clinotron effect is absent in the linear mode, since the amplification factor is maximized at zero angle between the beam and the surface of the slow-wave structure. In the large-amplitude mode, an obliquely incident beam, on the contrary, enhances the interaction efficiency. This is associated not only with the fact that partial layers of an obliquely incident beam propagate through the region where the HF field of the surface wave is largely localized, but also with weakening of nonlinear effects of bunching and energy exchange between the beam and the HF field. Comparative analysis of the efficiency of the clinotron effect in the modes of backward-wave oscillation and forward-wave amplification is performed.

The steady states of a 1D electron flow of electrons interacting with their self electric field are studied. A system of equations taking into account the hydrostatic pressure is reduced to a first-order nonlinear equation; partial solutions of this system are obtained. The possibility of exceeding of the ion sound velocity by ions is demonstrated. The behavior of a flow described by the adiabatic state equation is considered.

The problem of minimization of the difference in the characteristic impedances of resonators designed from sections of smoothly irregular and stepwise irregular transmission lines, which have distributions of initial eigenfrequencies important for practice, is solved. This problem is solved using the parametric synthesis method in which resonator eigenfrequencies are used as independent variables. It is shown that stepwise irregular resonators have lesser differences in the characteristic impedances than smoothly irregular resonators. A characteristic feature of synthesized resonators, their tendency to most simple shapes, is found. A set of synthesized stepwise irregular resonators is presented and their main characteristics are described. Using features of the obtained solutions, a simple method for the design of stepwise irregular resonators with minimum difference in the characteristic impedances is proposed, which allows one to expand in future the set of resonators suitable for practical applications.

A superconducting integrated receiver (SIR) (superheterodyne receiver) is developed for detection of radiation in a frequency range of 450–650 GHz. The SIR is used as a detector in the Terahertz Limb Sounder (TELIS) instrument that is mounted on a high-altitude balloon for the study of the atmospheric composition in the terahertz frequency range using limb sounding. The TELIS instrument and its detectors are described, and several results of the measurements in Polar Regions in 2009–2014 are presented