Abstract. Metallic waveguide with lenses periodically located inside it is investigated. Lenses are considered as phase correctors. Shape of lenses is determined by minimization of the ohmic losses of the basic mode.

Abstract. Beam waveguide consisting of identical circular diaphragms is considered. Additional losses of the basic mode, caused by random transversal shifts of diaphragms, variations of their inclination or radius, and axis turns, are calculated.

Abstract. A method of computer simulation of beam guides with random shifts of lenses is proposed. The method is an extension of the beam approach by accounting the diffraction losses at the lens edges. Statistical analysis of the guides is made.

Abstract. A beam guide consisting of circular lenses with quadratic phase correction is considered. The lens focal lengths providing minimal diffraction losses of the basic mode at given mean-square lens shifts is calculated.

Abstract. A method of the computer simulation of nonconfocal beam guides with random transversal lens shifts is proposed. Statistical assemblies of beam guides are modeled and investigated. Optimal focal lengths of lenses at given mean-square lens shifts is calculated by statistical analysis.

N. N. Voitovich, V. V. Semenov. Quasioptical lines as feeders. Radio Engineering and Electronic Physics. v.15, No.4, 1970 (Transl. from Radiotekhnika i Elektronika, v.15, No.4, 1970, p. 697-704).

Abstract. An iterative method of calculation of lens shapes in multilens quasioptical line transforming one given field (on the exciting aperture) into second given field (on the receiving aperture) is proposed and numerically realized. The method consisst in successive improvement of separate lenses shape using a specialyl transformed expression of the functional to be maximize (normalized inner product of given and obtained field distributions on the receiving aperture). Numerical results concerning mutuall transformations of different field distributions are shown.

Abstract. A method of investigation of irregular quasioptical lines (with lenses or mirrors as phase correctors) for electromagnetic power transmission is described in the review form. Random transverse shifts of the correctors are considered as main irregularities in the line. Numerical simulation of irregular lines with the next statistical analysis is used. One of the obtained results is a damping effect consisting in decreasingf the distance between the beam center and guide axis in irregular guide with limited corrector sizes in comparison with such distance in the guide with infinite correctors.

Abstract. A method for solving the problem on excitation of a vertical-nonhomogeneous fluid layer by point source is proposed. The field inside layer is expressed in the form of discrete series of functions with separated variables. The functions of vertical coordinate are the same as in the normal modes, but horizontal coordinate functions have more completed integral form. The method is illustrated on a model example.

Abstract. The method proposed before for calculating the field in underwater canal is used for solvving the problem about the field distribution in the waveguide with thin dielectric walls. The waveguide is excited by the cosinusoidally distrobuted field. Numerical results concerning the field distribution in wide ranges of geometrical parameters are shown.

Abstract. The method proposed before is applied to the concrete problem about propagation of monochromatic field of point source in layer with given distribution of sound velocity at different frequencies. The method permits to calculate the field distribution in the region beginning from very small distance from source and ending by asymptotic conditions. Method is effective at small and intermediate frequencies.

Abstract. A new approach to investigation of normal mode in dielectric waveguide at high frequency is presented. This approach permits to reduce the problem of normal modes calculation to the analogous problem for waveguide with metallic walls, having the same cross section shape. Modes of the two polarizations are separated and difference between their phase velocitie is calculated. As an example, the fiber with regular dielectric prop is investigated.

Abstract. The method based on minimization of boundary conditions residual is used for calculating the normal modes in dielectric waveguides with complicated cross-section shapes. Waveguides with square, triangular, and lentil-like cross-sections are investigated.

Abstract. In the review form, methods of mathematical analysis of regular dielectric waveguides having arbitrary cross section and arbitrary filling, are described. Some general properties of modes are determined. A variational technique as a method for solving the corresponding homogeneous problems is given. Three asymptotical cases (small jump of permittivity, high frequencies, low frequencies) are investigated in detail. In particular, it is established that in the first two cases the transversal magnetic field is linear polarized if degeneration is absent. Close to the critical frequency, the mode dispersive equation has the same form as for HE_1m in the circular waveguide. A case of three-component waveguide with arbitrary shape of wave-leading vein is considered too.

Abstract. A method for analysing the eigen modes in embedded channel waveguide is described. The method is based on using transversal components of magnetic field as unknown functions in homogeneous eigen value problem. In the case when difference between dielectric permittivities of the substrate and channel is small, this method permits to obtain some general results (such as linear polarization of eigen modes for arbitrary cross section shape etc.) analytically. Numerical results for some shapes of embedded channel are presented.

Abstract. Surface modes in circle dielectric waveguide with permittivity having an arbitrary piecewise continuous depending on the radial coordinate as well as slow azimuthal depending e(r,j) are considered. In the case e = e(r), algorithm consists in reducing the Maxwell equations to ordinary equations set. In this case the leaky-waves are also considered. In the case e = e(r,j), the perturbation method is used. Numerical results concerning a few concrete profiles of permittivity distribution are presented.

Abstract. A segment of the quasioptical line consisting of a series of sloped semitransparent mirrors is considered as a radiation system. The problem consists in determining the variable parameters (reflection and transmission factors) of the mirrors, which provide forming a given directivity pattern by reflected beams. The modulus of normalized inner product of given and obtained patterns is used as an optimization criterion. An iterative algorithm for solving this problem is proposed. The algorithm improves the parameters of all mirrors by turn. A special transformations of the criterion expression permit to minimize the calculation expenses for this procedure. Numerical results concerning lines of 4 and 10 mirrors are presented.

Abstract. In the review form, the method and results of the quasi-optical radiating system synthesis is presented. The system consists of a set of inclined semitransparent mirrors having the reflection and transmission factors variable along their surfaces. The problem consists in defining these factor to obtain the given directivity pattern. The scheme of algorithm as well as some numerical results are shown.

Abstract. Wave scattering problems in irregular waveguides are investigated. The proposed algorithm for solving such problems is based on the reduction of the scattering problem to an interior boundary value problem in the irregular section.This problem is solved in general form by the boundary integral equation method and then the solutions in regular and irregular sections are matched.

Abstract. The methods and algorithms of the amplitude distribution synthesis needed for increasing the Wireles Power Transmission (WPT) efficiency are discussed. It is shown that WPT efficiency increases not only of the uniform or taper distribution bat also when the field intensity is raised at the enges of the radiating apertures. In this case the receiving antenna (rectenna) is illuminated uniformly enough and the level of the near side lobes is essenciely decreased. Peculiarities of requirements to the field are discribed. Some numerical results concernig the optimal field distributions on the antenna and in the rectenna plane are presented.

Abstract. Two bicriterion optimization problems consisting in minimization of functionals, describing the energy and ecology requirements (transmission efficiency, surface usage, side radiation) are considered. The numerical method is proposed and results are presented.