Denoising of MST RADAR Signal usingCWT and Overlapping Group Shrinkage

Existing algorithmsare generally denouncing the existence of clusters with large amplitude coefficients. The L1 norm as well as other distinct models of sparsity does not attract a cluster tendency (group sparsity). In the light of a minimisation of convex cost work fusing the blended norm, this work introduces the technique "overlapping group shrinking." The groups are completely overlapping in order to abstain from blocking relics. A basic minimization calculation, in light of progressive replacement, is inferred. A straightforward strategy for setting the regularization boundary, in view of constricting the noise to a predefined level, is portrayed in detail by combining OGS with one of the most powerful mathematical tool wavelet transforms. In fact, the CWT coefficients are processed by OGS to produce a noise-free signal. The CWT coefficients are also processed.The proposed approach is represented on MST RADAR signals, the denoised signals delivered by CWT combined with OGS are liberated from noise.

Download Full-text

Estimating the Instantaneous Frequency of Linear and Nonlinear Frequency Modulated Radar Signals—A Comparative Study

Sensors ◽

10.3390/s21082840 ◽

2021 ◽

Vol 21 (8) ◽

pp. 2840

Author(s):

Hubert Milczarek ◽

Czesław Leśnik ◽

Igor Djurović ◽

Adam Kawalec

Keyword(s):

Instantaneous Frequency ◽

Early Warning Systems ◽

Vital Role ◽

Estimation Methods ◽

Radar Signal ◽

Nonlinear Frequency ◽

Modulation Recognition ◽

Electronic Warfare ◽

Time Frequency ◽

Radar Signals

Automatic modulation recognition plays a vital role in electronic warfare. Modern electronic intelligence and electronic support measures systems are able to automatically distinguish the modulation type of an intercepted radar signal by means of real-time intra-pulse analysis. This extra information can facilitate deinterleaving process as well as be utilized in early warning systems or give better insight into the performance of hostile radars. Existing modulation recognition algorithms usually extract signal features from one of the rudimentary waveform characteristics, namely instantaneous frequency (IF). Currently, there are a small number of studies concerning IF estimation methods, specifically for radar signals, whereas estimator accuracy may adversely affect the performance of the whole classification process. In this paper, five popular methods of evaluating the IF–law of frequency modulated radar signals are compared. The considered algorithms incorporate the two most prevalent estimation techniques, i.e., phase finite differences and time-frequency representations. The novel approach based on the generalized quasi-maximum likelihood (QML) method is also proposed. The results of simulation experiments show that the proposed QML estimator is significantly more accurate than the other considered techniques. Furthermore, for the first time in the publicly available literature, multipath influence on IF estimates has been investigated.

Download Full-text

Application of He’s Variational Iteration Method to Nonlinear Integro-Differential Equations

Zeitschrift für Naturforschung A ◽

10.1515/zna-2010-0507 ◽

2010 ◽

Vol 65 (5) ◽

pp. 418-430 ◽

Cited By ~ 1

Author(s):

Ahmet Yildirim

Keyword(s):

Differential Equations ◽

Iteration Method ◽

Variational Iteration Method ◽

Mathematical Tool ◽

Variational Iteration ◽

He’S Variational Iteration Method ◽

Powerful Mathematical Tool

In this paper, an application of He’s variational iteration method is applied to solve nonlinear integro-differential equations. Some examples are given to illustrate the effectiveness of the method. The results show that the method provides a straightforward and powerful mathematical tool for solving various nonlinear integro-differential equations

Download Full-text

Denoising of MST Radar Signal Using Multi-Band Wavelet Transform with Improved Thresholding

2018 Second International Conference on Inventive Communication and Computational Technologies (ICICCT) ◽

10.1109/icicct.2018.8473060 ◽

2018 ◽

Cited By ~ 1

Author(s):

G. Chandraiah ◽

T. Sreenivasulu Reddy

Keyword(s):

Wavelet Transform ◽

Radar Signal ◽

Mst Radar ◽

Multi Band

Download Full-text

Determination of the Limit Cycle by He’s Parameter-Expansion for Oscillators in a u3 / (1 + u2) Potential

Zeitschrift für Naturforschung A ◽

10.1515/zna-2007-7-807 ◽

2007 ◽

Vol 62 (7-8) ◽

pp. 396-398 ◽

Cited By ~ 4

Author(s):

Li-Na Zhang ◽

Lan Xu

Keyword(s):

Exact Solutions ◽

Limit Cycle ◽

Limit Cycles ◽

Expansion Method ◽

Nonlinear Oscillators ◽

Mathematical Tool ◽

Parameter Expansion ◽

Parameter Expansion Method ◽

Powerful Mathematical Tool

This paper applies He’s parameter-expansion method to determine the limit cycle of oscillators in a u3/(1+u2) potential. The results are compared with the exact solutions. This shows that the method is a convenient and powerful mathematical tool for the search of limit cycles of nonlinear oscillators.

Download Full-text

Application of He's Variational Iteration Method to Solve Semidifferential Equations of th Order

Mathematical Problems in Engineering ◽

10.1155/2008/627983 ◽

2008 ◽

Vol 2008 ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

Asghar Ghorbani ◽

Abdolsaeed Alavi

Keyword(s):

Iteration Method ◽

Present Method ◽

Variational Iteration Method ◽

Convergent Series ◽

Mathematical Tool ◽

Spline Method ◽

Weak Nonlinearity ◽

Variational Iteration ◽

He’S Variational Iteration Method ◽

Powerful Mathematical Tool

He's variational iteration method is applied to solve th order semidifferential equations. Comparison is made between collocation spline method based on Lagrange interpolation and the present method. In this method, the solution is calculated in the form of a convergent series with an easily computable component. This approach does not need linearization, weak nonlinearity assumptions, or perturbation theory. Some examples are given to illustrate the effectiveness of the method; the results show that He's method provides a straightforward and powerful mathematical tool for solving various semidifferential equations of the th order.

Download Full-text

On soft ordered ternary semihypergroups

International Journal of Algebra and Statistics ◽

10.20454/ijas.2018.1417 ◽

2018 ◽

Vol 7 (1-2) ◽

pp. 27-39

Author(s):

Muhammad Farooq ◽

Asghar Khan ◽

Muhammad Izhar ◽

Bijan Davvaz

Keyword(s):

General Framework ◽

Mathematical Tool ◽

Soft Sets ◽

Powerful Mathematical Tool

Theory of soft sets proposed by Molodtsov as a general framework for reasoning about vague concepts is a powerful mathematical tool for modelling various types of uncertainties. In this paper, we introduce the notions of intersectional soft subsemihypergroup, intersectional soft left (lateral, right) hyperideal of ordered ternary semihypergroups and related properties are investigated. We present characterizations of right weakly regular ordered ternary semihypergroups by means of intersectional hyperideals.

Download Full-text

A Detection Method of Radar Signal by Wavelet Transforms

Fourth International Conference on Fuzzy Systems and Knowledge Discovery (FSKD 2007) ◽

10.1109/fskd.2007.18 ◽

2007 ◽

Cited By ~ 3

Author(s):

Shanwen Zhang ◽

Jianbo Fan ◽

Lidan Shou ◽

Jinxiang Dong

Keyword(s):

Wavelet Transforms ◽

Detection Method ◽

Radar Signal

Download Full-text

Magnetosheath dynamic pressure enhancements: occurrence and typical properties

Annales Geophysicae ◽

10.5194/angeo-31-319-2013 ◽

2013 ◽

Vol 31 (2) ◽

pp. 319-331 ◽

Cited By ~ 45

Author(s):

M. O. Archer ◽

T. S. Horbury

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Wavelet Transforms ◽

Large Amplitude ◽

Statistical Study ◽

Average Duration ◽

Dynamic Pressure ◽

Random Events ◽

Fractional Increase ◽

The Magnetic Field

Abstract. The first comprehensive statistical study of large-amplitude (> 100%) transient enhancements of the magnetosheath dynamic pressure reveals events of up to ~ 15 times the ambient dynamic pressure with durations up to 3 min and an average duration of around 30 s, predominantly downstream of the quasi-parallel shock. The dynamic pressure transients are most often dominated by velocity increases along with a small fractional increase in the density, though the velocity is generally only deflected by a few degrees. Superposed wavelet transforms of the magnetic field show that, whilst most enhancements exhibit changes in the magnetosheath magnetic field, the majority are not associated with changes in the Interplanetary Magnetic Field (IMF). However, there is a minority of enhancements that do appear to be associated with solar wind discontinuities which cannot be explained simply by random events. In general, it is found that during periods of magnetosheath dynamic pressure enhancements the IMF is steadier than usual. This suggests that a stable foreshock and hence foreshock structures or processes may be important in the generation of the majority of magnetosheath dynamic pressure enhancements.

Download Full-text

Exact Explicit Traveling Wave Solution for the Generalized (2+1)-Dimensional Boussinesq Equation

ISRN Applied Mathematics ◽

10.5402/2011/419678 ◽

2011 ◽

Vol 2011 ◽

pp. 1-10

Author(s):

Libing Zeng ◽

Keding Qin ◽

Shengqiang Tang

Keyword(s):

Traveling Wave ◽

Boussinesq Equation ◽

Nonlinear Partial Differential Equations ◽

Mathematical Physics ◽

Traveling Wave Solution ◽

Mathematical Tool ◽

Extended Tanh Method ◽

Physical Problems ◽

Tanh Method ◽

Powerful Mathematical Tool

The sine-cosine method and the extended tanh method are used to construct exact solitary patterns solution and compactons solutions of the generalized (2+1)-dimensional Boussinesq equation. The compactons solutions and solitary patterns solutions of the generalized (2+1)-dimensional Boussinesq equation are successfully obtained. These solutions may be important and of significance for the explanation of some practical physical problems. It is shown that the sine-cosine and the extended tanh methods provide a powerful mathematical tool for solving great many nonlinear partial differential equations in mathematical physics.

Download Full-text