Том 59, № 5 (2016)
- Год: 2016
- Статей: 5
- URL: https://journals.rcsi.science/0735-2727/issue/view/10871
Article
QWIP focal plane array theoretical model of 3-D imaging LADAR system
Аннотация
The aim of this research is to develop a model for the direct detection three-dimensional (3-D) imaging LADAR system using Quantum Well Infrared Photodetector (QWIP) Focal Plane Array (FPA). This model is employed to study how to add 3-D imaging capability to the existing conventional thermal imaging systems of the same basic form which is sensitive to 3–5 µm(mid-wavelength infrared, MWIR) or 8–12 µm (long-wavelength infrared, LWIR) spectral bands. The integrated signal photoelectrons in case of short integration time is required to transmit laser pulses with higher energy in order to obtain photoelectrons nearest those values obtained from the background photoelectrons in thermal imaging system with the longer interval of time. Since the operating conditions of the proposed system are of low levels for speckle diversity and high levels of signal photoelectrons, it was shown that the signal obeys the Gaussian probability density function. The evaluation of system performance of the proposed model shows that it needs a detector with low dark current and high transmitted energy to obtain satisfactory parameter values.
Modeling of the seven-terminal transformer implemented in the LTGC-QO
Аннотация
In this paper a seven-terminal transformer has been designed. We have suggested its equivalent-circuit model. This transformer has a primary coil with a center tap and two secondary coils. Based on this transformer, a low-cost transformer-based gate-coupled quadrature oscillator (LTGC-QO) using 0.18 µm CMOS technology has been developed. The LTGC-QO consumes 7 mW at 1 V power supply. The simulated phase noise at 1 MHz offset is–116.3 dBc/Hz. The chip area is 400×500 µm.
Algorithm for synthesis of efficient S-boxes based on cellular automata
Аннотация
A method for synthesis of efficient schemes of S-boxes based on cellular automata satisfying the main criteria of cryptographic quality has been proposed. The cellular automata rules making it possible to obtain S-boxes satisfying the criterion of maximum avalanche effect were found.
Single-sideband quadrature angle modulation
Аннотация
In this article we describe a modulation technique of the angular component of the signal with the quadrature angle modulation (QAgM), which is aimed to narrow the spectrum width using the signals with single-sideband quadrature modulation as a modulation signal. This allows one to reduce the spectrum width of the signal compared to the spectrum width of the signal with QAgM.
Calculation of frequency and power characteristics of the composite metal-dielectric resonator using the method of partial regions
Аннотация
A new method for calculating the frequency and power characteristics of different modes of a microwave metal-dielectric resonator has been proposed. The results of measurements of experimental specimens are presented that are in good agreement with calculation results. The relationships of the frequency and power characteristics of a resonator as a function of its geometrical and electrophysical parameters were obtained by using the method of partial regions. A high sensitivity of the main mode resonant frequency to the thickness of air inhomogeneity was detected. In this case the introduction of inhomogeneity increases the resonator Q-factor. Thus, the proposed design can be used as a high-Q tunable resonator.