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The universities in Bulgaria operate in a very dynamic environment. The Ministry of Education and Science (MES) changes annually the requirements that their systems must meet. Changes can be small and affect only parts of the information systems in use or impose fundamental changes. To cope with this challenge, each university has a choice - either to move to a high level of digitalization or to maintain a minimum digitization of processes, so that no correction is needed in them, thus increasing the hours of work...

A directional coupler is a passive device designed to divide the power between its outputs in a given ratio. The value of this ratio depends on the resistances of the segments with which the device is assembled. It is important to understand how the miniaturization efficiency of a 3 dB directional coupler varies at different operating frequencies. Modeling and calculation of the characteristics of the devices was carried out in a specialized program Cadence AWR. The first step in the work was the design of taps ac...

Directional couplers implemented on two pairwise identical segments of the transmission line, have only one working bandwidth. In order to organize the performance of the structure on two ranges or more, it is necessary to make design changes to the standard device. For example, for operation at two frequencies, idle plumes are added to the design of the coupler. However, this has further increased the dimensions of the coupler, especially at low frequencies, and in some cases the design may be practically unsuita...

Directional couplers are widely used in microstrip technology, but their dimensions are tied to the operating frequency. Since the smaller the frequency, the longer the longitudinal length of the quarter-wave segments and the greater the overall dimensions of the coupler. For this reason, use miniaturization, which allows to reduce the area occupied by the device on the substrate, with negligible loss in performance. In addition, there is an economy of the material used in the manufacture of the microstrip device....

Microstrip directional couplers are made on microwave substrates, which consist of various dielectric materials. With a decrease in the operating frequency, the dimensions of the coupler increase, and more material is required for their manufacture. To reduce the consumable material, you can use different approaches to miniaturize the couplers, this will reduce the size of the device while maintaining its characteristics. So this article presents the results of research to reduce the occupied area of a flat crosso...

Microstrip devices have found wide application in various fields of radio engineering. However, such devices are made on dielectric substrates from various materials - glass,mica, ceramics, etc. In the process of manufacturing microstrip devices, it is possible to use, as etching method, this removal of excess copper coating, and removal of copper coating with special equipment, for example a milling machine . As a result, at various stages of manufacturing, material waste remains in large quantities, a solution f...

Miniaturization of microwave devices, such as directional couplers, filters, switches, etc., is an important practical problem due to the trend of integration of portable and small high-frequency electronics. In this paper, we consider the technology of developing a miniature microstrip device, which can be used in small space satellites and other aircraft, for which mass and dimensions are important. Modeling was carried out in the program for electrodynamics analysis of radio electronic devices in the NIAWR Desi...