V. V. Tikhonov

Model of Dielectric Constant of Bound Water in Soil for Applications of Microwave Remote Sensing - Abstract

The paper suggests a model of dielectric properties of bound water in wet soils. The application of the model to the description of dielectric and radiophysical properties of wet soils in microwave electromagnetic range is considered. The comparisons of theoretical and experimental dielectric constants provided show good reliability of the suggested model.

Radiophysical and Dielectric Properties of Ore Minerals in 12--145 GHz Frequency Range

The paper discusses a retrieval technique of complex permittivity of ore minerals in frequency ranges of 12{38GHz and 77{ 145GHz. The method is based on measuring frequency dependencies of transmissivity and re∞ectivity of plate-parallel mineral samples. In the 12{38GHz range, the measurements were conducted using a panoramic standing wave ratio and attenuation meter. In the 77{145GHz range, frequency dependencies of transmissivity and re∞ectivity were obtained using millimeter-band spectrometer with backward-wave oscillators. The real and imaginary parts of complex permittivity of a mineral were determined solving an equation system for frequency dependencies of transmissivity and re∞ectivity of an absorbing layer located between two dielectric media. In the course of the work, minerals that are primary ores in iron, zinc, copper and titanium mining were investigated: magnetite, hematite, sphalerite, chalcopyrite, pyrite, and ilmenite.

Satellite microwave radiometry of sea ice of polar regions: a review

This is a review of methods of passive microwave satellite monitoring of the sea-ice cover in polar regions. We briefly describe the microwave radiometers launched into the Earth’s orbit and provide data used in studies of Arctic and Antarctic sea ice. We give a detailed description of currently used algorithms for determining the sea-ice concentration and cover in polar regions according to satellite microwave radiometry. The methods for constructing these algorithms and their related drawbacks are considered. The final section of this paper briefly analyzes the studies that compare current algorithms with each other, with radar data, infrared data, and data of visual ship observations.

Integrative algorithm of determining ice conditions in Polar Regions by data of satellite microwave radiometry (VASIA2)

In this paper, a new algorithm for determining the concentration of the ice cover in Polar Regions by data of satellite microwave radiometry is considered. The technique of its construction is described in detail; it cardinally differs from the technique of creating present-day algorithms. The new algorithm demonstrates good results in determining the concentration of the ice cover in Polar Regions. The algorithm permits one not only to obtain maps of ice concentration, but also to determine areas of puddles covering the ice-cover surface in summer months. The algorithm is easy-to-use and requires no additional or fitting parameters. At the end of the work, advantages and disadvantages of the new algorithm are discussed.

Kramers–Kronig analysis of the optical constants of magnetite, pyrite, and chalcopyrite in the microwave range

The optical constants of a series of ore minerals (pyrite, magnetite, and chalcopyrite) have been analyzed in the microwave range using the Kramers–Kronig method. The spectral dependences of the reflectance of these minerals in a wide frequency range (from deep UV to microwave) have been plotted based on numerous experimental data from different sources. These dependences made it possible to calculate the optical constants of the minerals under study in a frequency range of 12–145 GHz and compare them with the results of the theoretical and laboratory studies published in different sources.

Peculiarities of stochastic regime of Arctic ice cover time evolution over 1987–2014 from microwave satellite sounding on the basis of NASA team 2 algorithm

The GLOBAL-RT database (DB) is composed of long-term radio heat multichannel observation data received from DMSP F08–F17 satellites; it is permanently supplemented with new data on the Earth’s exploration from the space department of the Space Research Institute, Russian Academy of Sciences. Arctic ice-cover areas for regions higher than 60° N latitude were calculated using the DB polar version and NASA Team 2 algorithm, which is widely used in foreign scientific literature. According to the analysis of variability of Arctic ice cover during 1987–2014, 2 months were selected when the Arctic ice cover was maximal (February) and minimal (September), and the average ice cover area was calculated for these months. Confidence intervals of the average values are in the 95–98% limits. Several approximations are derived for the time dependences of the ice-cover maximum and minimum over the period under study. Regression dependences were calculated for polynomials from the first degree (linear) to sextic. It was ascertained that the minimal root-mean-square error of deviation from the approximated curve sharply decreased for the biquadratic polynomial and then varied insignificantly: from 0.5593 for the polynomial of third degree to 0.4560 for the biquadratic polynomial. Hence, the commonly used strictly linear regression with a negative time gradient for the September Arctic ice cover minimum over 30 years should be considered incorrect.