多光束傅里叶望远镜成像质量主要因素分析

Introduction of dominating factors of multiple beam FT imaging quality

傅里叶望远镜在对深空暗弱目标成像方面有着独特的优势,但传统的3光束方阵成像扫描时间过长,只能对静止目标成像。为了在几秒之内对运动目标进行高分辨率成像,已经出现了几种不同类型的多光束发射阵列配置方案。在均匀分布排列中,T形配置是目前冗余度最小的结构之一。本文以6光束T形发射配置为例,简单介绍了傅里叶望远镜成像原理,依据T形发射阵列平面与空间频率平面的对应关系,分析了空间频率对成像质量的影响,验证T形发射阵列傅里叶望远镜成像优势,并进行了计算机仿真。得到了不同信噪比条件下的重构图像,通过在相同信噪比条件下和方阵列重构图像对比,成像质量完全满足要求且缩短了成像时间。仿真结果对室内和室外实验有着一定的指导作用,同时也为更多光束及其他发射阵列配置提供了参考。

Fourier Telescopy （FT）is an active imaging technique that has a unique advantage for high resolution of deep space object which is very small and dim. The traditional three square beam imaging＇s scan time is too long and it is suitable only for stationary targets. To carry out high resolution imaging for moving targets within a few seconds, there have been several different types of multi-beam emission array configuration. T-type configuration is one with the least redundant structures. This paper uses T-type and 6 beam launching configuration to introduce the principle of Fourier imaging telescope. The relationship between T-emission array plane and the spatial frequency plane is derived. By analyzing the impact of spatial frequency on image quality, the advantages of T-type Fourier imaging telescope array are verified. Through computer simulation, the reconstructed images under different conditions are obtained. Image quality can meet the requirements and imaging time is shorter at the same SNR. It provides a guide line for the indoor and outdoor experiments and also provides a reference for more beam and other emission array configuration.