An analytic expression of the two-frequency mutual coherence function (MCF) was derived for a two-dimensional random rough surface. The scattered field was cal-culated by the Kirchhoff approximation, which is valid in...An analytic expression of the two-frequency mutual coherence function (MCF) was derived for a two-dimensional random rough surface. The scattered field was cal-culated by the Kirchhoff approximation, which is valid in the case that the radius of curvature of the surface is much larger than the incident wave length. The scatter-ing problem of narrowband pulse was investigated to simplify the analytic expres-sion of the two-frequency MCF. Numerical simulations show that the two-frequency MCF is greatly dependent on the root-mean-square (RMS) height, while less de-pendent on the correlation length. The analytic solutions were compared with the results of Monte Carlo simulation to assess the accuracy and computational efficiency.展开更多
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 turbulen...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.展开更多
基金the National Natural Science Foundation of China (Grant No. 60571058)the National Defense Foundation of China (Grant No. 51403020505DZ0111)
文摘An analytic expression of the two-frequency mutual coherence function (MCF) was derived for a two-dimensional random rough surface. The scattered field was cal-culated by the Kirchhoff approximation, which is valid in the case that the radius of curvature of the surface is much larger than the incident wave length. The scatter-ing problem of narrowband pulse was investigated to simplify the analytic expres-sion of the two-frequency MCF. Numerical simulations show that the two-frequency MCF is greatly dependent on the root-mean-square (RMS) height, while less de-pendent on the correlation length. The analytic solutions were compared with the results of Monte Carlo simulation to assess the accuracy and computational efficiency.
基金supported by the National Natural Science Foundation of China(Grant Nos.61172031,61271110 and 61102018)the New Scientific and Technological Star of Shaanxi Province Funded Project(Grant No.2011KJXX39)the Natural Science Foundation of Shaanxi Province education office,China(Grant No.12Jk0955)
文摘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.
