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Considered in this paper are the methods of measurement uncertainty elimination using a phase method. A microwave-based device for the measurement of small distances on the basis of phase radar methods is presented in this paper.
The paper presents the results of design, manufacture and research of a microwave detector for detecting the pipe corrosion under an optically opaque coating and protective coating separation. The detector operates in the 5 mm wave band. A minimum diameter of the detected defect is 5-8 mm with an antenna horn aperture diameter of 60 mm. The antenna horn diameter may be changed. The device consists...
According to the order from OAO Gazprom, a radar level meter was developed for hydrocarbon materials and commercial products in tanks of a height up to 20 meters with a fixed roof or a floating cover. As a level meter YPMA-01 is designed for operation within control and data acquisition systems using an RS-485 interface. Site tests are at the final stage at Gazprom facilities, and RF Gostekhnadzor...
A meter for measuring liquid dielectric properties is described. The possibility of developing instruments for determination of liquid mixtures is demonstrated taking milk as an example.
This paper describes a technique to improve the accuracy in measurements of dielectric constants of liquids and granular materials. Two pieces of low loss dielectric material (plugs) are placed inside a waveguide to house the sample under measurement. The expression for the S/sub 21/ transmission parameter is derived here to take into account the multiple reflections within the plugs. The S-parameter...
The actual spatial distribution of the luminescence intensity of a microwave discharge in oxygen at different distances from the microwave energy input band was studied with the method of optical emission spectroscopy. The examinations were carried out in a plasma generator on the basis of a ring waveguide slot antenna.
The development results of a vector network analyzer (VNA) with quadrature mixers, which give the opportunity to measure S-parameters over a frequency range of 25-37 GHz, are presented.
The results of a computer simulation of measurement error of multiport microwave phase-measuring meter of complex reflection coefficient are considered. Mathematical model of a multiport transducer and statistical characteristics of measurement errors of module and argument of complex reflection coefficient of termination are represented.
Image deconvolution method based on the Tichonoff's theory of ill-posed problems is applied to the retrieval of images distorted by the instrument transfer function influence.
The possibility of the shot-term local forecast of atmospheric fronts conditioning anomalous radio wave propagation in the atmosphere boundary layer is shown. A temporary and spatial scale of front originating precursors by SODAR and RASS sounding is determined.
Antenna design for ground penetrating radar (GPR) requires to take into account a number of features related to subsurface sensing. Usually, such antennas are placed very closely to the object surface under investigation. They should be wideband to ensure good resolution, capable to operate on low frequencies to provide reasonable penetration depth, and be sufficiently sensitive and portable. Here...
To design microwave technological installations procedures based on the probability approach are offered. Ways of constructing probability models and methods of enriching figures of merit at their usage are considered. Examples showing the productivity of the probability approach are presented.
Local transformations of mixed cubic/hexagonal BN films under the action of electric field of STM probe have been observed. If a magnitude of voltage pulses U/sub bias/ exceeded a threshold value, the STM action results in a local conducting protrusion with a height of the 10% film thickness, and a lateral size of about the film thickness. The film was peeled off the substrate at high voltages. It...
Broadband microstrip filters based on quarter wave irregular resonators were investigated. The possibility of realization of miniature devices with fractional bandwidth up to 100% and with highly selective properties was shown.
The regularities in behaviour of damping poles observed for a frequency response (FR) of two-pole microstrip structure consisting of irregular resonators, concerning design parameters, are investigated. The filters with adjacent and diagonal connection to transmitting lines with equal bandwidths and distinguished by a type of prevailing coupling between resonators at the passband frequencies , are...
The rigorous solution of the problem excitation of a non-symmetrical reentrant resonator with partial dielectric filling by H/sub p0/ mode is received. The resonant phenomena at trapped modes are analyzed and the influence of a structure geometry and dielectric permittivity of an insertion on their Q and position is cleared up. The analytic solution of the problem is found.
Bismuth, antimony and its alloys are the typical representatives of a class of semi-metals, the electrical conductivity of which is 10/sup 2/-10/sup 3/ times lower than is usual for metals conducting well an electrical current. The alloys of bismuth with antimony have semiconductor properties in a wide range of structures at temperatures below 77 K. However, they are insulators at temperatures close...
The distribution of the electric field in planar film-substrate GaAs devices under backgating is considered. It is shown that backgating can make the film exhibit a long-length region of a quasi-uniform electric field exceeding the threshold of N-type negative differential mobility.
The investigation results of K/sub L/ stop-band filter based on wave-slot line are represented. The principle characters of such structures are the high attenuation level in stopband (around 30-40 dB), relatively low attenuation level in a pass-band (it is within 2 dB) and ability for manufacture.
Two variants of design of microwave phase shifters based on thin BSTO film for /spl sim/60 GHz frequency range are presented. Microstrip phase shifter demonstrates figure of merit F=22 deg/dB and continuous phase-shift up to /spl Delta//spl phi//spl ap/220 deg. Finline phase shifter demonstrates F=32 deg/dB and /spl Delta//spl phi//spl ap/250 deg.
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