V. V. Glamazdin

Improved differential Ka band dielectrometer based on the wave propagation in a quartz cylinder surrounded by high loss liquid under test

The differential dielectrometer was designed to measure small differences in complex permittivity (CP) of two high loss liquids at frequency 32.82 GHz. The measurements are fully computer-aided with the exception of liquids filling and draining in the measurement cells. The time of one measurement cycle does not exceed 3 min. The dielectrometer is easy-to-work and can be used under the conditions of scientific and industrial physical–chemical laboratories. The sensitivity of the difference in the phase coefficients of the electromagnetic waves propagated in the measurement cells is better than 0.05% and that of the attenuation coefficient is of the order of 0.2%. The dielectrometer contains two measurement cells that are dielectric quartz cylinders surrounded by high loss liquids. We developed the CP calculation algorithm using the known CP of the reference liquid and the difference coefficients of complex wave propagation in the cells. The origins of the measurement errors are studied in detail and recommendations were made to avoid some of them. The dielectrometer can be used to express the identification of wine and must authenticity by means of their CP values. The CP measurement results for solutions of some substances that make wine and must composition are obtained. The possibility of using the dielectrometer for the detection of added water in wines or musts is shown.

Combined reflector - lens monopulse antenna

The combined reflector-lens antenna having the common monopulse feed system is proposed for changing the sum and difference patterns width by turning of lamellate subreflector. Such an antenna allows one to improve a target detection probability with the same tracking accuracy. Information for antenna designing is done. The prototype antenna measurements are discussed.

Characteristics of the wavegude to quasioptical or dielectric resonator couplings

The comparison of experimental characteristics for two type of the open resonator coupling elements has been done. The measurements of the characteristics of a number of DR coupling elements has been carried out. The physical interpretation of obtained results has been done on the basis of the analysis of the quasioptical open resonator coupling carried out earlier.

Ka-Band Ground-Based Noise Waveform SAR

We present main results of design and investigations of Ka-band ground based interferometric SAR which uses continuous noise waveform as a probe signal and may operate in both monostatic and bistatic regimes. Synthetic aperture antennas enable to design a portable, light weight, easy to mount device with high speed of operation suitable for SAR imaging in quasi-real time while Ka-band noise waveform signals provide all-weather high resolution, high electromagnetic compatibility and interference immunity. Experiments have shown a rather high stability and repeatability of the measurements due to both the high quality of the equipment and advanced signal processing methods. The SAR system designed is an innovative instrument for solving new tasks of precise remote monitoring of various large objects, such as sealing of big halls, dams, bridges, TV towers, hangars, etc.

Waveguide longitudinal narrow wall slot radiating between baffles. Matching analysis

For of applications of waveguide-slot antennas, it is important to know the radiation characteristics of the slot in a rectangular waveguide wall radiating into a parallel-plate waveguide (PPW). In this work the properties of a longitudinal slot in the narrow wall of a rectangular waveguide radiating into a PPW are investigated. A model of a waveguide-slot radiator is presented and an accurate mathematical analysis provided. It is shown how to improve and optimize the matching of the considered radiators.

Determination method of water-glucose solution concentration at microwaves

We have presented the practical application of complex permittvity dielectromerty method to identify the glucose amount in water solution for modelling the determination of the glucose amount in human blood. We used disigned by us the waveguide-differential dielectrometer for the complex permittivity determination of high loss liquids such as water and water solutions. The complex permittivity of glucose water solution as a function of the glucose concentration was determined for the concentration from 0 to 100 mmol/L. It was shown that at the increase of glucose concentration in water solution their real and imaginary parts of the complex permittivity decrease monotonically.

Dielectrometry of pharmaceutical ingredient solutions at microwaves

The practical application of dielectrometry method to identify the pharmaceutical ingredients was held. The proposed waveguide-differential dielectrometer is used for the complex permittivity determination of high loss liquid such as water and water solutions in the millimeter wave range. This method allows a real-time determination of pharmaceutical ingredient content in water solution by measuring values of wave attenuation and phase coefficients difference in the differential measurement cavity. The complex permittivity of anatoxin, penicillin, gentamicin, lincomycin and glucose in fluid form as a function of the concentration was determined. The dielectric properties of various pH solutions have been determined as well. The sensitivity measurement have been detected of the water — glucose solution for its real and imaginary parts equal to 1.12 and 0.68 mmol/L, respectively.

Patterns of the three-band feed for a small VLBI radiotelescope reflector antenna

The results of an experimental study of patterns of the three-band feed for a small VLBI2010 compatible radio telescope reflector antenna are presented. Differences of the behavior of experimental three-band feed patterns and requirements specification for feed-prototype [1] are brought to light. A new engineering solution of the three-band feed unit has been suggested.

KA-Band, P-I-N switchable antenna array system

An original electrically switchable, Ka-band antenna array system has been recently developed, produced, and tested. The system consists of four identical sections, which are connected to radar transmitter/receiver by means of a high-power, multipole P-i-N switch. The introduced P-i-N switch enables for a fast electrical scanning of the antenna beam what essentially extends possible areas of the antenna system application. The antenna system is used in a helicopter collision avoidance, surveillance, and weather radar. This paper describes design features of the antenna system, its main characteristics, results of its testing, and the antenna integration in the radar.

2D tape scanner for microwave holography

The arrangement and operation principle of a new type 2D scanner antenna for radioholographic systems enabling 3D imaging is described. Design of such antennas and some results of their testing are presented.