3-mm wavelength range radar altitude sensors

In this study, we analyse the specific features of design of 3-mm wavelength range radar altitude sensors based on domestic-made super high frequency modules М55323 and М55328. Some results of full-scale tests are given.

STUDY OF INTERACTION OF SUPER HIGH FREQUENCY WAVES WITH GRAIN

The paper considers the interaction of ultrahigh-frequency waves with moist grains, in which the moisture information is represented as a function of two variables: the attenuation and phase shift of the electromagnetic wave. Wet material is represented as consisting of three flat layers: water, dry matter and air. Based on uncomplicated calculations, the conversion functions are derived and the influence of moisture, temperature and density coupling forms on the error of moisture conversion is studied.

Mathematical model of colostrum defrosting in super-high-frequency generator equipped

The paper is devoted to development and parameters studying of two-resonator super-high-frequency (SHF) generator based on continuous flow principle of action. It is equipped with two quasi-stationary toroidal resonators; so it allows to separate such processes of cattle colostral milk treatnent as defrosting and heating and thus to ensure both the electromagnetic safety and the high electric field strength. In order to improve efficiency of the cattle colostrum defrosting/heating performed by its exposure to the super-high frequency electromagnetic field, the methodology was developed for the SHF generator designing. It includes, firstly, development & studying of mathematical models based on due consideration of the phase transitions and, secondly, the structural designing of the SHF generator working chamber with examination of its effective operating modes. The mathematical model is proposed of the electromagnetic waves interaction with the raw material (colostral milk) being in different physical states. With aid of the electric field strength control (by the generators power changing) and the gap adjustment in the capacitor part of the resonators (by smooth movement of the common perforated base), it is possible to achieve the equipment capacity up to 170… 200 L/h. The energy expenses are 0.025 (kWh)/kg.

Antena mikrostrip berpolarisasi lingkaran pada daerah ultra high frequency dan super high frequency

Beberapa tahun terakhir terjadi peningkatan penggunaan teknologi komunikasi WiFi dan teknologi komunikasi 5G. Kedua teknologi tersebut akan terus melayani kebutuhan manusia secara simultan. Oleh karena itu, sangat dibutuhkan sebuah peralatan yang mampu mengakomodasi kedua jaringan yang berada pada frekuensi kerja daerah ultra high frequency (UHF) dan super high frequency (SHF) tersebut dalam satu perangkat khususnya antena untuk meningkatkan efisiensi penggunaan perangkat. Pada makalah ini telah dilakukan perancangan dan simulasi sebuah antena yang bersifat dual-band menggunakan metode multi-patch dual-frequency antennas, serta penambahan metode truncated corner untuk menghasilkan polarisasi lingkaran. Dari hasil simulasi diperoleh bahwa antena mikrostrip dual-band dengan metode truncated corner memiliki frekuensi kerja 2,378 MHz dan 3540,8 MHz, bandwidth minimal 50 MHz, pola radiasi unidirectional, gain minimal 3 dBi, dan axial ratio mendekati 1,00.

Electrical characterisation of higher order spin wave modes in vortex-based magnetic tunnel junctions

NiFe-based vortex spin-torque nano-oscillators (STNO) have been shown to be rich dynamic systems which can operate as efficient frequency generators and detectors, but with a limitation in frequency determined by the gyrotropic frequency, typically sub-GHz. In this report, we present a detailed analysis of the nature of the higher order spin wave modes which exist in the Super High Frequency range (3–30 GHz). This is achieved via micromagnetic simulations and electrical characterisation in magnetic tunnel junctions, both directly via the spin-diode effect and indirectly via the measurement of the coupling with the gyrotropic critical current. The excitation mechanism and spatial profile of the modes are shown to have a complex dependence on the vortex core position. Additionally, the inter-mode coupling between the fundamental gyrotropic mode and the higher order modes is shown to reduce or enhance the effective damping depending upon the sense of propagation of the confined spin wave.