Using the polarization characteristics of a target and its underlying surface one can change the target contrast range.
As the target one can use the compact and discrete structures with different characteristics to reflect electromagnetic
An important problem, solved by the adaptive polarization lidar, is to determine the availability and identification
of different targets based on their polarization characteristics against the background of underlying surface, which polarization
characteristics are unknown.
Another important problem of the adaptive polarization lidar is a search for the objects, which polarization characteristics
are unknown, against the background of underlying surface, which polarization characteristics are known. The
adaptive polarization lidar makes it possible to determine the presence of impurities in sea water.
The characteristics of the adaptive polarization lidar undergo variations, i.e., polarization characteristics of a sensing
signal and polarization characteristics of the receiver are varied depending on the problem to be solved. One of the
versions of construction of the adaptive polarization lidar is considered.
The increase of the contrast in the adaptive lidar has been demonstrated by the numerical experiment when sensing
hydrosols on the background of the Rayleigh scattering, caused by clear water.
The numerical experiment has also demonstrated the increase of the contrast in the adaptive lidar when sensing at
two wavelengths of dry haze and dense haze on the background of the Rayleigh scattering, caused by the clear atmosphere.
The most effective wavelength was chosen.
In the radio optically active detection and ranging of objects a signal from an
investigated object at the noise background should be recognized. This noise may be the
background created both by a foreign source and the background from the underlying
surface, on which the object being studied is located.
Using the source polarization of a sensing signal of optical radar and polarization
elements of the receiver, we can increase the value of the signal from the studied object
as compared with the noise background.
The versions of the efficiency increase of research tools of active radio and optical
sensing are considered at the following conditions:
1. The background from the external source is known.
2. The scattering matrix of underlying surface creating the background is known.
3. The scattering matrix of underlying surface creating the background is unknown.
4. The external source and underlying surface present the background source:
a) the Stokes vector of external source and the scattering matrix of underlying surface
b) the Stokes vector of external source and the scattering matrix of underlying surface
c) the Stokes vector of external source is known and the scattering matrix of underlying
surface is unknown and vice versa.
The propagation of electromagnetic field in the isotropic substance is considered. The corrected Lorentz model of a simple harmonic
oscillator is justified, which takes into account the action of magnetic component of electromagnetic field. It is shown that the
corrected Lorentz model, except for the term, proportional to electric field intensity, contains the term proportional to the derivative of the electric field intensity. The last term takes into account the action of magnetic component of electromagnetic field.
The paper describes the operation of an instrument recording a signal from a radiation source scattered by the medium with the
known scattering phase matrix. If the recording is made in the absence of background, the Stokes vector parameters are determined
So of a radiation source, providing the maximum intensity of a scattered signal. If the recording is made with the availability of the background, characterized by the Stokes vector parameters Sf, the Stokes vector parameters S0 are determined of the radiation source
and the receiver polarization characteristics, providing on its sensitive element the maximum ratio between the radiation source scattered signal intensity and the background intensity.
The experimental data provide support for the conclusion that the atmosphere and aerosol particle form a linear dynamic system. The behavior of aerosol particle in the coordinates: the logarithm of undersaturation coefficient of water vapor and the logarithm of the relation of the equilibrium particle size to the dehydrated particle size is given by the straight line segments. Each segment is characterized by its coefficient of condensation activity. Aerosol particle of chemically pure substances and sometimes the atmospheric aerosol particles are denoted in this plot by a straight line corresponding to the condensation activity coefficient, being equal to infinity. Now we denote the relative humidity corresponding to this segment as a specific point. The precipitation of water molecules on aerosol particle is due to a tendency of the surface to decrease its energy, i.e. to decrease the surface tension. With increasing the relative humidity from zero to the specific point the adsorption takes place, i.e. water molecules cover the particle surface with a monolayer. At the specific point the interphase surface tension of the particle-monolayer system becomes equal to zero, i.e., absorption begins. If in the atmosphere the relative humidity is supported, which is slightly less than the value of the specific point, during a long period of time, then the heat energy of atmospheric molecules is large enough for splitting a particle to small parts and for changing significantly the particle size distribution over a long period of time. In this case the reversible process of coagulation is very slow because the energy gain is low at the particle coalescence.
The medium where the electromagnetic field propagates, in relation to the parameters characterizing the electric field, is found to form a linear dynamic system. The magnetic field parameters are related in a similar way. Based on this statement the Maxwell macroscopic equations are derived from the microscopic equations. The relative dielectric constant is a positive real function of complex variable and can be represented by the fractional-rational function. The paper describes the mathematical grounds of the substance polarization Lorentz model. Besides its correction is given taking account of the magnetic field action. A consideration of the relative dielectric constant in space of a complex variable enables, us, along with the Kramers-Kronig formula, to obtain a series of new relationships for its real and imaginary parts. We derived the expression of the coefficient of transfer of a plane wave through the propagation medium. The requirements are given to which the transfer coefficient must satisfy when the signal transfer is not distorted.
The aerosol particle size depends on the air relative humidity. In the range of air relative humidity from 0.2 to 0.93, the equilibrium particle size is determined by the Kasten formula. This formula is an asymptotic approximation of the solution of the linear differential equation at t equals (infinity) . The first order differential equation describing the particle size variation dynamics establishes a new aerosol parameter, name the time constant.
Molecular and aerosol scattering of laser radiation, propagating in the atmosphere, makes it possible to visualize it in space. This phenomenon can be used for navigation in the navy, air force and astronautics. The laser radiation scattering is known to be used in the visual laser beam systems. The scattered laser radiations is small as compared with direct laser radiation and safe for sight. The method being developed uses the scattering effect and enables one to create the instrumental laser beam systems for pilotage alone fairways and approach canals in coastal waters and seaports.