MONITORING OF COASTAL ECOSYSTEMS BY METHOD OF REMOTE SENSING IN THE SHORT-WAVE RANGE OF RADIO WAVES

Author(s):  
Sergej Belov ◽  
Sergej Belov ◽  
Ija Belova ◽  
Ija Belova ◽  
Stepan Falomeev ◽  
...  

A new method for estimating the parameter noncoherent signal/noise K of ionospheric signal is offered. A comparative analysis is carrying out. This new method exceeds an order of magnitude widely used standard one by analytical (relative) accuracy of determining a parameter K. It has the same order as the well-known coherent methodology.

Author(s):  
Sergej Belov ◽  
Sergej Belov ◽  
Ija Belova ◽  
Ija Belova ◽  
Stepan Falomeev ◽  
...  

A new method for estimating the parameter noncoherent signal/noise K of ionospheric signal is offered. A comparative analysis is carrying out. This new method exceeds an order of magnitude widely used standard one by analytical (relative) accuracy of determining a parameter K. It has the same order as the well-known coherent methodology.


2017 ◽  
Vol 7 (2) ◽  
pp. 216-231
Author(s):  
Sergej Yurievich Belov

Monitoring of the earth's surface by remote sensing in the short-wave band can provide a quick identification of some characteristics of coastal Arctic ecosystems. This band range allows to diagnose subsurface aspects of the earth, as the scattering parameter is affected by irregularities in the dielectric permittivity of subsurface structures. This method is based on the organization of the monitoring probe and may detect changes in these environments, for example, to assess hazardous natural phenomena, assessing sustainability, as well as some man-made hazards and etc. The problem of measuring and accounting for the scattering power of the earth's surface in the short-range of radio waves is important for a number of purposes, such as e.g diagnosing properties of the medium, which is of interest for geological, environmental studies. In this paper, we propose a new method for estimating the parameters of incoherent signal/noise ratio. The paper presents the results of comparison of the measurement method from the point of view of their admissible relative analytical errors. The new method is suggested. Accuracy new method on the order exceeds the widely-used standard method. Interpretation of the data is based on a statistical multiplicative model of the signal. Testing the method of obtained a signal/noise ratio in this model was produced by the example of a double reflection of the probe signal from the SW ionosphere in a vertical sounding (when using a satellite, the signal passes twice through the atmosphere and ionosphere). In this paper, a sensitivity of the model parameters was studied. To obtain the necessary experimental data, the pulse method of coherent reception was used. Analysis of analytical error of estimation of this parameter allowed to recommend a new method instead of standard method. A comparative analysis showed that the analytical (relative) accuracy of the determination of this parameter by a new method exceeded the widely-used standard method by the factor of ten.


2017 ◽  
Vol 20 (3) ◽  
pp. 118
Author(s):  
I Z Klimov

Выполнен анализ вариантов построения широкополосных систем связи, отличающихся типами используемых сигналов и способами их обработки. Показано, что требуемый уровень потенциальной помехоустойчивости в многолучевом канале обеспечивает ЧР-ШПЭ. Реальный уровень помехоустойчивости соответствует потенциальному значению только при оптимальном когерентном сложении ветвей разнесения и идеальной синхронизации. На основе использования ШПС-РС с усложненной структурой может быть реализована ШСС с высоким уровнем качества передачи информации и защиты от организованных помех, в которой за счет уменьшения времени передачи радиограммы реализуется передача с частотно-временным разнесением путем повторов передачи на заданных частотах.


Author(s):  
B. G. Shadrin ◽  
◽  
D. E. Zachateyskiy ◽  
V. A. Dvoryanchikov Dvoryanchikov ◽  
◽  
...  

2021 ◽  
pp. 095745652199987
Author(s):  
Magaji Yunbunga Adamu ◽  
Peter Ogenyi

This study proposes a new modification of the homotopy perturbation method. A new parameter alpha is introduced into the homotopy equation in order to improve the results and accuracy. An optimal analysis identifies the parameter alpha, aimed at improving the solutions. A comparative analysis of the proposed method reveals that the new method presents results with higher degree of accuracy and precision than the classic homotopy perturbation method. Absolute error analysis shows the convenience of the proposed method, providing much smaller errors. Two examples are presented: Duffing and Van der pol’s nonlinear oscillators to demonstrate the efficiency, accuracy, and applicability of the new method.


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