Conformal Array Geometry for Hemispherical Coverage

Conformal arrays may be a viable solution in many antenna applications requiring a wide angular coverage with sufficiently high directivity values, so it is worth comparing different 2D conformal array geometries to satisfy these requirements. To this end, first, the singular value decomposition (SVD) of the radiation operator is exploited to determine the maximum directivity values an array can reach in the whole observation domain. A numerical study based on the maximum directivity and, hence, on the SVD is then proposed to select the array geometry complying with some given requirements. Therefore, the performances achievable by some array geometries (a semi-circumference, a trapezoidal, and an angle array) are analyzed, and the one assuring a better hemispherical coverage is suggested. Furthermore, such an SVD-based study is usefully exploited to determine which panels of a multi-faceted array must be fed to reach some assigned specifications.

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Steganography Arabic Text Based on Natural Language Process Documents

Journal of Education College Wasit University ◽

10.31185/eduj.vol1.iss25.132 ◽

2018 ◽

Vol 1 (25) ◽

pp. 457-480

Author(s):

Hanaa M. Ahmed ◽

Maisa'a A. A. Khohder

Keyword(s):

Singular Value Decomposition ◽

Natural Language ◽

Rapid Development ◽

Arabic Language ◽

Singular Value ◽

Secret Message ◽

Linguistic Steganography ◽

The One ◽

Value Decomposition ◽

Natural Language Process

: Obscurity is a main reason whereas computers can not know natural language. It have made great transaction steps trend developing instrument to morphological and syntactic analyzers for Arabic . One of the manners used in security areas is steganography. The rapid development of steganography scripts, it is a large security and confidentiality problem, it becomes necessary to find appropriate protection because of the significance, accuracy and sensitivity of the data during transmitted. In this research is offer in a new method and to use one level to hide, this level is hiding by embedding and addition. The one level is embed a secret message twice, one bit in the LSB in the FFT and the addition of one kashida and add Single-Double Quotation in the same secret message. Using Random Singular Value Decomposition (RSVD) is NRG to find positions that are hiding within the text. Linguistic steganography is covering all the techniques that deal with using written natural language to hide secret message. in this research presents a linguistic steganography for scripts written in Arabic language, using kashida, Single-Double Quotation and Fast Fourier Transform on the bases of using new technique entitled Random Singular Value Decomposition (RSVD) as allocation to hide secret message. The proposed approach is an attempt to present a transform linguistic steganography using one level for hiding to improve implementation of kashida and Single-Double Quotation , and improve the security of the secret message by using Random Singular Value Decomposition (RSVD). Are testing this method in terms of security and capacity, transparency, and robustness and this is way better than previous methods. The proposed algorithm ideal steganography properties.

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Removing Direct Wave of Through-Wall Radar Based on Singular Value Decomposition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.301-303.442 ◽

2011 ◽

Vol 301-303 ◽

pp. 442-446

Author(s):

Hui Xu ◽

Bang Yu Li ◽

Li Yao

Keyword(s):

Singular Value Decomposition ◽

Decomposition Method ◽

Simulation Software ◽

Singular Value ◽

Echo Signal ◽

Direct Wave ◽

Wave Signal ◽

Singular Value Decomposition Method ◽

The One ◽

Value Decomposition

The problem of target detection which is affected by the direct wave is discussed in this paper. Singular Value Decomposition method is proposed for removing the direct wave. The echo signal is decomposed by use of Singular Value Decomposition method and the one-order eigenvalue of the eigenvalue matrix is set to zero, then the related components of echo signal are removed. The direct wave signal can be removed effectively using this method, and most of the target components of signal are preserved in the process of removing direct wave signal. HFSS simulation software is used for modeling and simulation, and the results show that the resolution of false target using Singular Value Decomposition method increases 11% compared with the Interference Canceling method for removing direct wave.

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