Xian Yang Normal College

Xianyang, China

Xian Yang Normal College

Xianyang, China

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Wang M.,Xian Yang Normal College | Li Y.L.,Xian Yang Normal College | Wang Y.,Beijing Institute of Environmental Characteristics | Xiang N.,Xian Yang Normal College | Xiang N.,Xidian University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2013

It has used the two-frequency mutual coherent function to study pulse scattering from one dimensional perfectly conducting rough surface. So this paper is mainly focused on that the analytical expressions for incoherent mutual function (MCF) for pulse scattering from one-dimensional random rough surface are obtained based on the Kirchhoff's approximation. According to the analytical solutions, numerical methods are shown that coherent and incoherent mutual function (MCF) change with the coherence bandwidth frequency difference and scattering angles in different incident angles incidence on laser (1.06μm) according to the mean of fluctuating heights and correlation length of the rough surfaces. And some important scattering characteristics of the coherent and incoherent mutual function (MCF) are be obtained in details. Our works is helpful when investigating the statistical characteristics of laser scattering fields of objects with rough surface. © 2013 SPIE.


Wang M.,Xian Yang Normal College | Meng X.-H.,Xi'an University of Technology | Li Y.L.,Xian Yang Normal College | Deng R.,Signature | Xiang N.,Xian Yang Normal College
2012 10th International Symposium on Antennas, Propagation and EM Theory, ISAPE 2012 | Year: 2012

The experimental measurement and image processing methods are combined to study the light scattering characteristic from the target, principle of the scaling ratio between the light scattering characteristic and the geometric dimension of the target is presented in this paper. The solar simulator is utilized as a light source which incidence the target with rough surface. The original experimental images must be measured by light receiver and data gathering system. Some image algorithms are be designed to process these experimental data. As a researching example, the imaging light scattering characteristic of two kinds of bigger and smaller simple targets include clubs, cylinders are discussed in detail. The image processed results are shown the scale ratio of the light scattering from target is proportional to its dimensional square. The important of our works is that the scaling rations of the light scattering characteristic can be used to make known the illumination of the whole dimensional detected target, which are useful for further study the complex target such as civilian industries, national defence, air and aero fields. © 2012 IEEE.


Wu P.,Xi'an University of Technology | Wang M.-J.,Xi'an University of Technology | Wang M.-J.,Xian Yang Normal College | Ke X.-Z.,Xi'an University of Technology | And 2 more authors.
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2014

The development of laser range profile, Doppler spectra and Range Resolved Doppler imaging technologies including the experiments, simulations and engineering applications have been summarized and reviewed in this paper. It was analyzed the problems of the laser radar imaging system which need to solve in experiments and models. The achievements and the key technologies of Range profile, Doppler spectra and Range Doppler imaging laser radar are reported in detail. Different typically theoretical simulated models have been built to show the last technologies of target recognition for laser radar in order to be based on the further studying on designing the laser radar imaging systems in many applications and offering the precise data of the detected target. © 2014 SPIE.


Gong Y.,Hunan University | Wang M.,Xian Yang Normal College | Gong L.,Xi'an Technological University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

Laser one-dimensional range profile, that is scattering power from pulse laser scattering of target, is a radar imaging technology. The laser two-dimensional range profile is two-dimensional scattering imaging of pulse laser of target. Laser one-dimensional range profile and laser two-dimensional range profile are called laser range profile(LRP). The laser range profile can reflect the characteristics of the target shape and surface material. These techniques were motivated by applications of laser radar to target discrimination in ballistic missile defense. The radar equation of pulse laser is given in this paper. This paper demonstrates the analytical model of laser range profile of cylinder based on the radar equation of the pulse laser. Simulations results of laser one-dimensional range profiles of some cylinders are given. Laser range profiles of cylinder, whose surface material with diffuse lambertian reflectance, is given in this paper. Laser range profiles of different pulse width of cylinder are given in this paper. The influences of geometric parameters, pulse width, attitude on the range profiles are analyzed. © 2015 SPIE.


Gong Y.,Hunan University | Zhu C.,Hunan University | Wang M.,Xian Yang Normal College | Gong L.,Xi'an Technological University
Proceedings of SPIE - The International Society for Optical Engineering | Year: 2015

This paper deals with the laser bistatic two-dimensional scattering imaging simulation of lambert cone. Two-dimensional imaging is called as planar imaging. It can reflect the shape of the target and material properties. Two-dimensional imaging has important significance for target recognition. The expression of bistatic laser scattering intensity of lambert cone is obtained based on laser radar eauqtion. The scattering intensity of a micro-element on the target could be obtained. The intensity is related to local angle of incidence, local angle of scattering and the infinitesimal area on the cone. According to the incident direction of laser, scattering direction and normal of infinitesimal area, the local incidence angle and scattering angle can be calculated. Through surface integration and the introduction of the rectangular function, we can get the intensity of imaging unit on the imaging surface, and then get Lambert cone bistatic laser two-dimensional scattering imaging simulation model. We analyze the effect of distinguishability, incident direction,observed direction and target size on the imaging. From the results, we can see that the scattering imaging simulation results of the lambert cone bistatic laser is correct. © 2015 SPIE.


Liu W.,Northwest University, China | Chang Q.-R.,Northwest University, China | Guo M.,Northwest University, China | Xing D.-X.,Northwest University, China | And 2 more authors.
Hongwai Yu Haomibo Xuebao/Journal of Infrared and Millimeter Waves | Year: 2011

The hyper-spectral reflectance of soil was measured by a ASD FieldSpec within 400~1000 nm, then treated with logarithmic transformation. First derivative of soil spectra with different scales of differential window were acquired and denoised by the threshold denoising method based on wavelet transform. From the first derivative of soil spectra, feature parameters used as indicators for soil organic matter content were extracted. Results show that: (1) When the number of the scale of differential window was set as W=1~5, it is difficult to identify the spectrum contour and response feature in first derivative of soil spectra because of much noise. (2) When W=6~15, noise in first derivative of soil spectra is partly removed, and spectrum contour is identified roughly. However spectral response feature resulted from different organic content levels can not be identified clearly. (3) When W=16~30, noise in first derivative of soil spectrua is removed effectively. The coefficient of correlation between organic matter content and feature parameter MDs 19 is 0.803. MDs 19 can be used as one of the best indicators for soil organic matter content.


Xiang N.,Xian Yang Normal College | Xiang N.,Xidian University | Wu Z.,Xidian University | Wang M.,Xian Yang Normal College
Science China: Physics, Mechanics and Astronomy | Year: 2014

The extended Huygens-Fresnel principle and Goodman model was utilized for target surface to derive the mutual coherence function (MCF) of a Gaussian beam reflected from an arbitrary rough target in atmospheric turbulence. According to the MCF, expressions of the mean irradiance and average speckle size at the receiver were obtained. The analysis indicated that the mean intensity is closely related to the ratio of root mean square (rms) height to the lateral correlation length. In addition, the speckle size at the receiver is associated with turbulence strength, propagation distance and roughness of the target. The results can be reduced to the result of a Gaussian beam illuminating rough target and scattering from a target in free space. © Science China Press and Springer-Verlag Berlin Heidelberg 2014.


Xiang N.-J.,Xidian University | Xiang N.-J.,Xian Yang Normal College | Wu Z.-S.,Xian Yang Normal College | Guo Q.-F.,Xidian University | Wang M.-J.,Xidian University
Journal of Quantitative Spectroscopy and Radiative Transfer | Year: 2015

The extended Huygens-Fresnel principle is used to develop a formulation for the backscattered intensity enhancement of a Gaussian Schell-model source beam through a weak turbulence. The results are shown that backscattered intensity enhancement factor of the reflected GSM beam is concerned with the coherence length of source, the wavelength, the size of target and wave structure function. In addition, the closed-form expressions can interpret backscattered intensity enhancement of plane and spherical wave scattered from a diffuse target. The results are illustrated by examples and compared with the previous work. © 2015 Elsevier Ltd.


Xiang N.-J.,Xidian University | Wu Z.-S.,Xidian University | Hua X.-X.,Xian Yang Normal College | Wang M.-J.,Xian Yang Normal College
Optik | Year: 2013

Based on extended Huygens-Fresnel principle and Goodman model for target surface, analytic expression is developed for the mutual coherent function (MCF) of a reflected Gaussian-beam from a semi-rough target in single-pass atmospheric turbulence. Then according to the MCF we derive expression about the mean intensity and average speckle size at the receiver. The analysis indicates that the mean intensity is closely related to the ratio of root mean square (rms) height to the lateral correlation length; in addition, the speckle size is associated with turbulence strength and roughness of target. Our results agree with well-known the limiting cases of perfectly smooth and Lambertian target. © 2013 Elsevier GmbH. All rights reserved.


Xiang N.,Xian Yang Normal College | Xiang N.,Xidian University | Wu Z.,Xidian University | Hua X.,Xian Yang Normal College | Wang M.,Xian Yang Normal College
Qiangjiguang Yu Lizishu/High Power Laser and Particle Beams | Year: 2014

We utilize the extended Huygens-Fresnel principle to make an analysis of the scattering of a Gaussian Schell-model beam from a diffuse target in a turbulent atmosphere. It is assumed that the wave structure function is dominated by the phase structure function. Using the cross-spectral density function of the GSM beam, the analytical expressions are developed for the mutual coherence function (MCF) of the speckle field at the receiver, and then time-delayed variance of the scattering intensity in strong turbulence is derived. From the normalized MCF, estimates are given for the speckle size at receiver. We also analyze the influences of the coherence length of the source, wavelength, and turbulence strength on the mutual coherence function. For a diffuse target, the speckle size is only determined by the waist width, the coherence length of the source and the turbulence strength. With the turbulence strength increasing, the speckle radius will decrease at the receiver. In weak turbulence, speckle radius is dominated by the value of source coherence.

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