Study on Clutter Model and Characteristics of Airborne Radar with Parabolic Conformal Phased Array

The studies on clutter modeling and suppression of airborne radar with a parabolic conformal array are uncommon due to the complexity of this type of antenna array configuration.The correct understanding of clutter characteristics for airborne radar with a parabolic conformal antenna array is the prerequisite and foundation of optimal suppression of this type of clutter.This paper establishes the model of clutter echo of airborne parabolic conformal phased array radar and analyzes the structure characteristics and the distribution features of this type of clutter.The simulation results show that this type of clutter has the following characteristics：1） The main lobe on the azimuth is seriously broadened,2） the power spectrum presents strong heterogeneity,and 3） the freedom degrees are high.Based on the existing related clutter suppression methods,we verified the correctness of the constructed clutter model.This work has an important guidance to further study on clutter suppression methods in airborne parabolic conformal array radar.

广东云开山国家级自然保护区鸟兽红外相机调查初报

2017年1月至2019年9月,我们在广东云开山国家级自然保护区3个观测样区布设61台红外相机,对兽类和鸟类多样性进行调查。共记录到野生兽类4目7科9种,鸟类6目14科34种,其中广东省新记录1种,为蓝绿鹊(Cissa chinensis),记录国家II级重点保护动物3种,为原鸡(Gallus gallus)、白鹇(Lophura nycthemera)和蓝绿鹊。相对多度较高的5种兽类依次为赤腹松鼠(Callosciurus erythraeus)、赤麂(Muntiacus vaginalis)、鼬獾(Melogale moschata)、野猪(Sus scrofa)和果子狸(Paguma larvata),相对多度较高的3种鸟类分别是紫啸鸫(Myiophoneus caeruleus)、虎斑地鸫(Zoothera dauma)和红嘴相思鸟(Leiothrix lutea)。通过对相对多度指数前三的鸟兽日活动节律观察分析,共发现4种典型昼行性动物(赤腹松鼠、紫啸鸫、虎斑地鸫和红嘴相思鸟)和1种典型夜行性动物(鼬獾)。赤麂日活动呈现两个高峰时段,分别为12:00–14:00和18:00–20:00。本研究评估了广东云开山国家级自然保护区部分兽类和鸟类资源现状,为保护区野生动物保护与管理提供了数据支持。