Ukrainian engineering and pedagogical academy, Kharkiv, Ukraine
Antenna for Navigational Shipborne Millimeter-Wave Radar
Substantiation of the use of a navigation radar-tracking station (NRTS) of a millimeter waveband of a mirror antenna in the form of a clipping from a paraboloid of gyration is given. The calculation of parameters of the antenna based on the requirements of wind loads reduction is presented. The possibility to manufacture a reflector element of the antenna system with a high accuracy is shown using rather simple technique.
14, Lenin Ave, Kharkiv, 61166, Ukraine
Minimally Allowable Power at the Input of Digital Optical Receiver Unit for the Systems of Optical Access
The formulas for calculation of the minimum optical power on the input of optical receiving devices (ORD) of digital systems of optical access (SOA) not depending on resistance of a photodetector for high-sensitive ORD are obtained. The reduction of a passband ORD results in reduction of the level of noise in ORD SOA. The boosting of spectral sensitivity on current of the photodetector makes it possible to decrease the noise
Extension of the Time Interval for Evaluation of Broadband Signal Delays in a Multichannel Acousto-Optic Correlator with Time Integration
V. Karazin National University of Kharkov,
4, Svoboda Sq., Kharkiv, 61077, Ukraine
Injection Regime of Antibarrier Metal-Semiconductor (m-n) Contact
The paper considers processes occurring in the space-charge (SC) region of antibarrier metal-semiconductor (m-n) contacts, that confine the injection current, as well as impede vanishing of contact potential difference Uk due to the direct voltage. The current buildup through the m-n contact after decreasing Uk to the minimum has been investigated.
A. Usikov Institute of Radio Physics and Electronics,
National Academy of Sciences of Ukraine
12, Academician Proskura Str., Kharkiv 61085, Ukraine
Power and Spectrum Perfomance of Quasi-Optical Solid-State MM-Wave Oscillator
Description of the corner-echelette resonator is provided. A two-dimensional waveguide model of the resonator under investigation is considered and some operating modes, in particular, quasi-fundamental oscillation modes with the field compression towards the resonator axis have been analysed. Gunn-diode oscillator characteristics are investigated. The oscillator is stabilised within the reactive-reflected circuitry which is excited on the quasi-fundamental mode. Short-time source frequency instability is of no less than 10-9 sec-1. Relative long-term frequency stability is dF/F ~ 10-8.
The Problem of Stability of a Parametric Loop with Positive Torsion Elements
1Kharkov National University of Radio Engineering and Electronics,
14, Lenin Ave, Kharkov, 61166, Ukraine
2Tavricheskii National University,
4, Vernadskogo Ave., Simferopol, 95007, Ukraine
Avalanche Features in Silicon Schottky-FETs in Accordance with Numerical Simulation Results
The numerical simulation results of initiation and dynamics of the avalanche breakdown in silicon Schottky-FETs are represented and analyzed in relation to the electric conditions and dimensions of the active region. The estimation of influence of the current crowding on current-voltage characteristics of Schottky-FETs has been carried out. Characteristic quantities of the Wunsch-Bell criterion at the heat breakdown in Schottky-FETs have been defined more exactly.