# Vol 16, No 1 (2013)

**Year:**2013**Articles:**15**URL:**https://journals.ssau.ru/pwp/issue/view/397

## Articles

### Spatial selectivity of a four-wave radiation converter based on thermodiffusion and electrostriction mechanisms of nonlinearity

#### Abstract

An analytic expression allowing to analyze the spatial selectivity of the four-wave converter based on thermodiffusion and electrostriction nonlinearities is obtained. Shown that the treatment of electrostriction leads to two object waves at small spatial frequencies in opposite phase with the waves that occur due to thermodiffusion nonlinearity. There is a spatial frequency at which the reflectivity of these waves is zero.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):6-11

### Magnetostatic waves in the gap between two ferromagnetic with longitudinal magnetizations that move relative to each other

#### Abstract

The propagation of a magnetostatic gap wave in a gap between two ferromagnetic with opposite longitudinal magnetizations is considered under the conditions for relative longitudinal displacement. It is shown that the view of dispersive dependences of a high-frequency and low-frequency modes of magnetostatic gap waves is considerably modified because of displacement of one of a crystals. At the same time the magnetic field of high-frequency mode in the gap displays «sensitivity» to relative longitudinal displacement of a crystals.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):12-18

### Synchronization of self-oscillator wich fractional feedback

#### Abstract

A model of self-oscillating system with a differential equation of motion of fractional order under the action of an external harmonic signal is proposed. Solutions of the equation of motion which correspond to the regime of steady-state synchronized oscillations and the regime of beats near the synchronization band are obtained in the quasiharmonic approximation. The amplitude frequency and phase-frequency characteristics of synchronization of fractional Van der Pol oscillator are analyzed. An analogy between the generator with a fractional feedback circuit and the generator with delayed feedback is established.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):19-23

### The effect of feedback on the Volterra series convergence radius

#### Abstract

This paper describes the destructive effects of both external and internal feedback on the convergence of the iterative process for finding the Volterra kernels in strongly nonlinear electronic circuits. There is investigated the location of the critical points at which the system loses its analytical properties, and Volterra series begin to diverge. In some cases the critical points for the Volterra series lie in the deep nonlinear region, in other cases these points are directly adjacent to the weakly nonlinear mode. It is found that the failure of the iterative process occurs at the negative and positive feedback, but the latter one limits the convergence radius much more.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):24-30

### Diffraction of electromagnetic waves on the spiral elements

#### Abstract

The diffraction of electromagnetic waves on the following structures: a single-pass cylindrical helix and the combination of left-and pravovintovoy cylindrical helix. The source of excitation acts linearly polarized plane wave vertical or horizontal polarization. The calculation is based on the integral representation of the electromagnetic field fine-wire structure, migrating to the surface of the radiating elements in the system of integral equations for the unknown current distributions. It is shown that the structure, which consists of combining left and pravovintovoy spirals, has a pronounced axial re-radiation, which is observed in a wide frequency.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):31-39

### Passage of fractal pulse in noisy fiber link with dispersion

#### Abstract

Consider the results of the numerical experiment to study the passage of fractional pulse through a single-mode optical fiber with the chromatic dispersion. Along with the desired signal transmitted masking noise signal. It is shown that for effective cleaning of the fractal signal from the noise at the output of the fiber-optic link is necessary along with the code to know the fractal signal dispersion coefficient of the optical fiber.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):40-46

### Nonlinear reflection ellipsmetry for an anisotropic uniaxial crystal then optical axis lies in the plane of incidence

#### Abstract

A new method of ellipsometry was considered – «Nonlinear ellipsometry», allowing to determine nonlinear characteristic of a medium. Angular spectra of nonlinear reflection ellipsometry for uniaxial crystals such as Beta-Barium Borate, Lithium Niobate, Proustite were calculated and plotted at different orientations of the optical axis. Also the high sensitivity of method in the diagnosis of the crystal parameters was showed.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):47-52

### The efficiency of systems of spatial radar signal processing on a clutter background with non-isotropic elements of a cylindrical array

#### Abstract

In conjunction with the problem of the target selection on a clutter background with quasi-continuous radiation, the analysis of the spatial radar signal processing is made. The analysis is made for a case of non-isotropic array elements. The calculation results of the optimized receiving antenna pattern and the attained signal-to-noise ratio for the confirmation of the efficiency of the cylindrical array system with the azimuth scanning rate increase are given.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):53-58

### Research of direction-finding pattern formed by linear array antenna with using of the Keipon’s algorithm

#### Abstract

The potentially obtainable direction-finding pattern characteristics with using of the Keipon’s algorithm for linear antenna array are analyzed in the article. There’re analytical ratios, establishing relation of antenna parameters (number of elements and element spacing) with direction-finding pattern performance (–3 dB power pattern width and side lobe level).

**Physics of Wave Processes and Radio Systems**. 2013;16(1):59-61

### Coupled slow-wave structures

#### Abstract

A generalized model of the coupled slow-wave structures (CSWS) formed by placed in parallel or coaxially impedance conductors, had been considered. Substituting obtained equivalent parameters in the «truncated» long-line dispersion equation made it possible deriving a dispersion equation and an expression for the opposite phase wave slowing down. It follows from the obtained relations that independently on the specific configuration of the impedance conductors, slowing of the opposite-phase wave in the CSWS may exceed many times slowing in one impedance conductor while saving a large enough wave impedance and a small loss in the conductors. It has been shown that the electric field energy concentration between impedance conductors and the magnetic field energy concentration outside conductors provides the significant increase in the effectiveness of RF heating and measuring providing the possibility of developing novel technologies and devices for industrial and medical applications.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):62-67

### About the features of the azimuthal oscillations in shielded dielectric resonator

#### Abstract

The features of azimuthal oscillations in a shielded leucosapphire resonator are considered. Investigated the dependence of oscillation characteristics from the parameters of the oscillating system. Described in detail the effect of the conversion of high-quality oscillations in low-quality oscillations when changing the aspect ratio of the cavity and dielectric resonator. Recommendations are given for the practical implementation of the considered construction of the resonator.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):68-79

### Calculation of phase coefficient and attenuation coefficient for Sommerfeld E_00 wave in a conductor of large radius

#### Abstract

Using the developed method for finding a solution to the dispersion equation for E_00 wave (Sommerfeld wave) in a cylindrical conductor of large radius with finite conductivity the dependences of phase coefficient and attenuation coefficient on frequency (f <= MHz) are calculated for the cylinder with radius of the Earth and material parameters of sea water (sigma_1 = (1–5) (Ohm m)^-1).

**Physics of Wave Processes and Radio Systems**. 2013;16(1):80-87

### The design of the wideband ferrite Y-circulators on lumped elements

#### Abstract

Possibility of creation of wideband VHF ferrite circulators on the lumped elements is shown by the expanded band of working frequencies, which is reached for the account of the optimised operating mode. The method of calculation of such circulators is offered.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):88-93

### The protector devices for UHF set with pin-diodes

#### Abstract

The computed and measured characteristics a protector devices for UHF-set are presented. In these devices have been used pin-diodes with different base, also «similar-teristor». The analyzed and measured results has proven to be an efficient tool in design on microwave devices.

**Physics of Wave Processes and Radio Systems**. 2013;16(1):94-97