二维综合孔径微波辐射计圆环结构天线阵 及其稀疏方法

本文介绍了圆环天线阵二维综合孔径微波辐射计的测量原理和反演算法,并通过模拟退火算法讨论了两种二维综合孔径微波辐射计圆环阵的稀疏方案,一种方案利用天线旋转,在半圆周上稀疏天线;另一种方案通过将空间频率采样点的均匀分布作为优化的约束条件,在全圆周上稀疏天线.结果显示两种设计较传统设计均有改进之处.对于半圆周天线而言,在积分时间允许的条件下,通过天线旋转与分时测量,天线阵可进一步稀疏.对于全圆周天线而言,与Y形天线阵结构相比,在同样的空间频率覆盖范围内,全圆周天线阵使天线单元数达到了最优.

Optimization on Circular Thinned Array for Two-Dimensional Synthetic Aperture Microwave Radiometer

The study on image theory and the retrieving algorithm of two-dimensional synthetic aperture microwave radiometer with circular antenna array is presented.Based upon simulated annealing algorithm,we will discuss two solutions of obtaining the ideal thinned array.One solution uses half-circle configuration with very much reduced number of elements and taking an image by rotating the array.The other solution selects element positions around the full circle to provide a roughly uniform coverage in the spatial frequency domain.The results show that both solutions have improved characteristics over the conventional design.For the half-circle case,if the integration time allows,with the rotation of the array and the limited time-shared measurements the number of elements can be further reduced to a great extent.For the full-circle case,the array can be thinned up to the least redundant number,which can never be reached by the most popular Y shaped array configuration under same spatial frequency coverage constraint.