Digital steganography is a kind of data security technique. In this paper, a new information hiding scheme was proposed. In this scheme, we embed secret message into still digital images based on (7, 4) Hamming Code a...
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In conventional single-antenna systems, differential modulation is useful when the knowledge of channel state information (CSI) is not available. Some time division multiple access (TDMA) wireless cooperative relay pr...
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Based on the Retinex method and the SIFT feature analysis, this paper presents a novel algorithm for hand vein recognition. First of all, the principle of the near-infrared hand vein image acquisition is introduced. S...
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Based on the Retinex method and the SIFT feature analysis, this paper presents a novel algorithm for hand vein recognition. First of all, the principle of the near-infrared hand vein image acquisition is introduced. Secondly, the Retinex method is used to normalize hand vein images, and the adaptive smoothing method is selected to estimate the illumination. Then gray cosine transform is used to enhance the discrimination of the skin and the vein in hand vein images. Thirdly, the SIFT feature analysis algorithm is used to extract the feature of hand vein. Finally, the match method of two hand vein images based on SIFT is given. A hand vein recognition system in Microsoft VC6.0 is also developed and the experimental results demonstrate the high efficiency of the proposed algorithm in runtime and correct recognition rate.
Some time division multiple access (TDMA) wireless cooperative relay protocols have recently been developed. The works about their symbol error rate (SER) performance, however, are limited to SER upper bounds or SER f...
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Some Time Division Multiple Access (TDMA) wireless cooperative relay protocols and their Symbol Error Rate (SER) performance have recently been developed. These works, however, are limited to SER upper bounds or SER f...
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Standard backprojection technique is used in typical through-wall synthetic aperture radar (TWSAR) image, it implicitly assumes infinite beamwidth, whereby the entire target area is illuminated and returns are collect...
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The finite difference time domain (FDTD) is a powerful method in electromagnetic simulation and also widely used in research of the metamaterials recently. In this paper a novel FDTD method based on split operator is ...
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In the paper, the authors derive the method of splitting plane wave FDTD (SP-FDTD) method for initiation of plane wave sources in the total-field and scattered-field (TF/SF) formulation of 3D FDTD (2, 4) scheme. By sp...
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An efficient SAR image fusion algorithm for multi-polarimetric images based on Directionlets transform is proposed. Directionlets transform is a new lattice-based multi scale analysis anisotropic multi-directional wav...
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ISBN:
(纸本)9781612847719
An efficient SAR image fusion algorithm for multi-polarimetric images based on Directionlets transform is proposed. Directionlets transform is a new lattice-based multi scale analysis anisotropic multi-directional wavelet transform. Firstly, several polarimetric images can be decomposed into low frequency coefficients and high-frequency coefficients with multi scales and multi-directions using the Directionlets transform. For the low-frequency coefficients, the average fusion method is used. For the each directional high frequency sub-band coefficients, the directive contrast and the larger value of region variance information measurement is used to select the better coefficients for fusion. At last the fused image can be obtained by utilizing inverse transform for fused Directionlets coefficients. Experimental results show that compared with traditional algorithm, the proposed algorithm can get better visual effect and the significant information of original image like textures and contour details is well maintained.
In wireless communication, the cooperative communications technology has been concern because of its advantages of spatial diversity. In particular, cooperative communication with a single relay is a simple, practical...
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In wireless communication, the cooperative communications technology has been concern because of its advantages of spatial diversity. In particular, cooperative communication with a single relay is a simple, practical technology for wireless sensor networks. In this paper, we analyze several simple network topologies. Under the condition of equal power allocating, the optimum relay locations are respectively determined by using symbol error rate (SER) formula. And these types of topologies are compared, the analysis results show that, Linear network topology has the best system performance, the system performance of isosceles triangle topology is better than that of equilateral triangle topology.
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