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621.374.33
Разработка
и исследование системы радиоимпульсной регенерации для устройств высокоскоростной
стробоскопической оцифровки
К. А. Бойков
Московский технологический университет
(МИРЭА),
119454, Москва, просп. Вернадского, 78
Статья поступила в редакцию 13 марта 2018 г.
Аннотация.
Показаны основные этапы разработки и проектирования схемы электрической
принципиальной системы радиоимпульсной регенерации для высокоскоростной стробоскопической
оцифровки, позволяющей восстановить и воспроизвести одиночный сверхкороткий
радиоимпульс нестационарной конфигурации в задачах радиовидения. Сформулировано
обоснование выбора электронной компонентной базы, приведен расчет основных
блоков и узлов системы. Построена схемотехническая PSpice-модель системы в
среде Proteus.
Исследована устойчивость циклогенеративного усилителя. Рассмотрен пример
регенерации сложного одиночного сверхкороткого радиоимпульса без несущего
частотного заполнения, полученного в результате отражения зондирующего сигнала от
идеально проводящей сферы. Выполнен корреляционный анализ исходного и
восстановленного импульсов, посредством модели строб-фрейм-дискретизатора в
графической среде имитационного моделирования Simulink.
Указаны основные недостатки системы и предложены пути их устранения.
Ключевые слова:
сверхкороткоимпульсный сигнал, циклогенеративная система, масштабно-временное
преобразование, строб-фрейм-дискретизация, радиовидение.
Abstract.
Stroboscopic reception eliminates the
possibility to process non-stationary ultrashort pulses, since a series of
absolutely identical pulses is needed to correctly restore the original time
profile. Reconstruction of the non-stationary ultrashort pulse signal from one
pulse will solve the concealment problems in the systems of the radio vision,
and will also allow to restore the reflection from the object that is rapidly
changing its position in space.
One of the methods for restoring
and reproducing a complex single ultrashort pulse can be considered the use of
a radio-pulse regeneration system (a cyclo-system). To confirm the functioning
of this system, its hardware implementation is necessary. For a detailed
demonstration of the basic principles of the operation of the radio-impulse
regeneration system, it is advisable to limit its operation in the frequency
band 20-200 MHz with the processing of a SCI with a duration of 5-50 ns, since
recording of shorter single pulses without the use of stroboscopic reception
methods is very difficult.
The selection and calculation of
the elemental base for constructing the electrical schematic diagram is
determined by the basic elements of the cyclo-system of the system - a
broadband amplifier and a high-speed turn-key.
Based on the main significant
parameters, the amplifier of the company Analog Devises - AD8000 is offered as
an amplifier, as a high-speed switch - the switch SPDT HMC197b (Analog
Devises). Also in the scheme is used digital delay and control on high-speed
inverters 74HС04 (Texas Instruments),
analog delay line on coaxial cable RG-213 with a wave resistance of 50 Ohm, the
length of which is calculated. The attenuator is selected as passive, with
ohmic total impedance of the arms, calculated on the basis of the load capacity
and the need to match the input and output of the video amplifier.
When the basic conditions for
signal regeneration are fulfilled and the input and output of the amplifier of
the cycling system are matched, the damped pulse is re-amplified through the
time of the delay line and the cycle repeats.
A model of a radio-impulse
regeneration system is constructed in a circuit simulation environment based on
the models of electronic components adopted in PSpice, for example, Proteus of
Labcenter Electronics. With the help of this model, one of the basic conditions
for the functioning of the cyclogenetic system has been checked: the absence of
an involuntary self-excitation of the amplifier of the system, that is,
stability. For this purpose, the phase-frequency characteristic of the
amplifier with feedback and the amplitude-frequency characteristic of the
amplifier without feedback in the entire frequency range of operation were
constructed. After checking and confirming the stability of the amplifier with
a phase and amplitude margin, the functioning of the developed system in the
regeneration mode of a complex single radio pulse obtained by reflection from
an ideally conducting sphere is shown.
Based on the generated pulses, the
original signal is reconstructed using a sampler-frame sampler model in the
Simulink simulation simulation environment, followed by a correlation analysis
of the original and reconstructed pulse.
The PSpice model of the radio pulse
regeneration system confirmed its viability, as well as the possibility of
restoring a complex non-stationary signal by a single pulse.
Keywords:
ultrashort impulse signal, cyclogenerative system, scale-time transformation,
strobe-frame-sampling, radioview.
Для
цитирования:
К.
А. Бойков. Разработка и исследование системы радиоимпульсной регенерации для
устройств высокоскоростной стробоскопической оцифровки. Журнал
радиоэлектроники [электронный журнал]. 2018. №3. Режим доступа: http://jre.cplire.ru/jre/mar18/6/text.pdf
DOI 10.30898/1684-1719.2018.3.2