MICROWAVE PROPAGATION AND SCATTERING IN A DENSE DISTRIBUTION OF NONTENUOUS SPHERES - EXPERIMENT AND THEORY

被引：36

作者：

MANDT, CE

KUGA, Y

TSANG, L

ISHIMARU, A

机构：

[1] Dept. of Electr. Eng., Washington Univ., Seattle, WA

来源：

WAVES IN RANDOM MEDIA | 1992年 / 2卷 / 03期

基金：

美国国家航空航天局; 美国国家科学基金会;

关键词：

D O I：

10.1088/0959-7174/2/3/004

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Controlled laboratory experimental results of coherent microwave propagation through a random medium are reported. The medium consisted of layers of styrofoam with spherical glass beads embedded at predetermined random positions generated by computer. The magnitude and phase of the transmitted field was measured over the frequency range 18-20.4 GHz for media with volume fractional densities ranging from 0.5% to 11%. The results are compared with independent scattering, Foldy's approximation, and the quasicrystalline approximation (QCA) using the solution of the Percus-Yevick (PY) equation for the pair distribution function. The effects of a size distribution are included. Experimental results indicate that at low densities, the measured extinction rate increases linearly with concentration in agreement with independent scattering. As concentration further increases, the extinction curve turns convex and is lower than independent scattering. However, it is higher than that predicted by QCA-PY. Using the known particle positions we have also computed the pair correlation function and good agreement is obtained with the Percus-Yevick approximation.

引用

页码：225 / 234

页数：10

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