Comparison of optical and millimeter wave imaging on speckle
Comparison of optical and millimeter wave imaging on speckle
复制标题
散斑光学成像与毫米波成像的比较
DOI：
10.1109/aps.2008.4619935
复制
发表时间：
2008
期刊：
影响因子：
--
通讯作者：
B. Nauwelaers
中科院分区：
文献类型：
--
作者：
Q. Feng;D. Schreurs;V. Tavakol;B. Nauwelaers
本文从波动的观点解释了散斑现象的起源。理论上认为，系统的有限功率收集能力是一阶因子，可以用无限大的透镜来解决，而较大的透镜无法避免传播过程中的光路衰落和干涉。Hadamard散斑抑制方法是处理电大尺寸粗糙度（多个波长）散斑的有效方法。在有源毫米波成像中，由于电小单元尺寸引起的功率问题可能是高分辨率的瓶颈。因此，Hadamard技术在实际的有源毫米波成像系统中是有条件有效的，但它往往最终表现得不如理论上的最佳。
In this paper, the origin of speckle phenomenon is explained from the wave point of view. The finite power collection ability of the system is considered to be the 1st order factor which can be solved by infinite large lens theoretically, while the path fading and interference of the wave during propagation can not be avoided by a larger lens. Hadamard speckle reduction approach is effective to deal with speckles generated by electrically large roughness (several wavelengths). In active millimeter wave imaging, the power issues due to electrically small cell size may be the bottleneck to high resolution. Therefore, Hadamard technique can be effective in practical active millimeter wave imaging systems conditionally, and it usually ends up underperforming to theoretical best.