Vol 20, No 1 (2017)

The paper considers the solution of the problem of plane linearly polarized electromagnetic waves reflection from a planar metamaterial layer consisting of thin-wire perfectly conducting two mutually orthogonal helices matrix. The dispersion model is built for considered metamaterial. The problem was solved by the partial areas method and solution was reduced to a linear algebraic equations system for the unknown reflection and transmission coefficients. The frequency selective investigated metamaterial properties were identified as a numerical analysis result. In particular, it is proved that the metastructure is a frequency selective screen for microwave radiation at some frequencies.

The experimental assessment of accuracy of measurement of coordin ates of radio-radiation of range of high frequencies goniometric and goniometric and range-metering is carried out by methods. Regularities of mean squared measurement errors of coordin ates of radio stations of meteo-information of airfield networks, standard frequencies and time, transmitters of telecode and continuous messages in different season and are probed days.

New discrete mappings of Thomson type self-oscillatory systems are offered. Mappings are received by method of structural synthesis with use of the sequences of discrete counting of pulse characteristics of the resonators which are a part of self-oscillatory systems. The method of the slow-changing amplitudes is used for the analysis of response characteristics of self-oscillations in the discrete time. The example of generation of self-oscillations with discrete mapping of the oscillator of Van der Pol is given.

The problem of practical application of Hall effect at microwave frequencies to measure of continuous and pulsed microwave power passing in a rectangular waveguide was considered. The analysis of contribution of Hall effect, thermopower and contact thermopower to summary output voltage of converter was carried out. Methods of reducing volume and the contact thermopower have been suggest. Samples of semiconductor microwave power converters based on Hall effect have been designed and constructed. The influence of microwave power level on the conversion factor has been studied. It was found that the conversion coefficient not altered in dependence of the microwave power from 0 to 10 W of continuous signal and from 0 to 3000 W of pulsed signal with duty cycle lower 0.08 %.

Currently, audio-video information can be transmitted by various communication systems such as WiFi, WiMAX, LTE, or 3G. Despite the fact that these systems fulfill their functions quite well, they are united by a common drawback - they are not designed to work in conditions of strong interference. To transfer audio-video information in the presence of strong interference, the authors have developed a data transfer system using spread spectrum signals. This article is devoted to the design, configuration and interface study of how to link this system with standard sources and receivers, both audio and video.