V.A. Tsarev – Dr.Sc. (Eng), Professor, 

Department «Electronic Devices», Yuri Gagarin State Technical University of Saratov

Е-mail: tsarev_va@mail.ru 

A.Yu. Miroshnichenko − Dr. Sc. (Eng), Associate Professor, Head of the Department «Electronic Devices»,  Yuri Gagarin State Technical University of Saratov

Е-mail: alexm@sstu.ru

А.V. Gnusarev – Post-graduate Student, 

Department «Electronic Devices», Yuri Gagarin State Technical University of Saratov

Е-mail: 19953@bk.ru

N.A. Akafyeva – Ph.D. (Eng) Associate Professor, 

Department «Electronic Devices», Yuri Gagarin State Technical University of Saratov

Е-mail: akafieva_na@mail.ru

M. A. Chernyshev – Post-graduate Student, 

Department «Electronic Devices», Yuri Gagarin State Technical University of Saratov Е-mail: tchernysheff.max@yandex.ru

To create low-voltage multi- beam klystrons operating at the frequencies of the Ku and K bands, it is necessary to move on to new principles of design and manufacturing technology for the resonator systems of these devices. However, the creation of such electrodynamic systems in the millimeter and submillimeter ranges is a difficult task. Classical designs of double-gap resonators have low manufacturability and low resistance to vibration. In this regard, the creation of miniature multi- beam klystrons, whose resonant elements, as well as TWT slowing systems, are made on printed circuit boards located perpendicular to the direction of motion of the electron beam, is of considerable interest. Such designs of electrodynamic systems provide high adaptability and good resistance to vibration. The aim of this work is to study the electrodynamic characteristics and parameters of multichannel two-gap photonic crystal resonators with fractal resonant elements “Sierpinski triangle” (MTGPCR). Such resonant systems are excited at the resonant frequencies of the fundamental and higher modes corresponding to antiphase (π) and in-phase (2π) RF voltages in the gaps at which it is possible to realize effective interaction with a multipath electron beam. 

The resonator interaction space is located inside the defect formed by a lattice of round metal rods. In the central part of the threedimensional defect on a suspended dielectric substrate there is a central electrode with 13 holes for transmitting electron beams, which is connected to two half-wave resonant conductors with fractal elements. The shape of this element is determined by the iteration number (K= 0,1,2) of the Sierpinski Triangle fractal. Three resonator designs with a fractal resonant conductor of zero, first and second iteration were investigated. The main electrodynamic parameters of the resonator were determined. It was established that in the investigated resonance system the antiphase and in-phase modes of oscillations have a frequency spacing of 6-7%. As a working mode, it is advisable to choose the in-phase type of oscillation. The optimal form of the fractal element is the fractal of the second iteration. The behavior of the resonant frequencies of the resonator as a function of the step of the photonic crystal lattice was also studied. The developed practical recommendations for choosing the optimal parameters of resonator designs can be used in the development of miniature klystron-type multi- beam devices operating as amplifiers, generators, or frequency multipliers.

Царев В.А., Мирошниченко А.Ю., Гнусарев А.В., Акафьева Н.А., Чернышев М.А. Миниатюрные двухзазорные фотонно-кристаллические резонаторы с фрактальными резонансными элементами, выполненными на печатной плате // Радиотехника. 2020. Т. 84. № 7(14). С. 41−49. DOI: 10.18127/j00338486-202007(14)-06.

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