运动状态下隐身飞行器的毫米波辐射机理与特性研究

The rapid development of aircraft stealth technology brings a great threat to national security. As a new target detection method, passive millimeter-wave (MMW) radiometric measurement has been paid more and more attention in the field of stealth aircraft detection. At present, the research on the MMW radiation characteristics of aircraft is mainly focused on the static characteristics. However, under the motion state, the physical parameters of stealth material and the distribution characteristics of plume flow field could be changed complexly. It will seriously affect the MMW radiation characteristics, and even bring some difficulties to target detection and identification. Based on the mechanism level, the MMW radiation characteristics of stealth aircraft will be investigated with “movement” as the core. Through studying the moving thermal effect, this project mainly studies the influence of the physical temperature on the MMW radiation of stealth material, and builds the mechanism model of stealth material MMW radiation; studies on the motion mechanism of the MMW radiation of tail plume flow; analyses the internal relations between and the motion state and the MMW radiation characteristics (i.e., polarization characteristics and spatial distribution characteristics); carries out the simulations and experiments. This project can lay a theoretical foundation for the target information acquisition and feature recognition in the practical application of anti-stealth detection, and provide the basis of stealth design for MMW radiation.

飞行器隐身技术的快速发展，给国家安全带来巨大威胁。作为一种新的目标探测手段，被动毫米波辐射测量用于隐身飞行器探测已逐渐受到国内外的高度重视。当前，飞行器目标毫米波辐射特性研究主要停留在静态特性上。然而，运动状态下的隐身飞行器，其表面隐身涂层材料物理参数和尾焰流场分布特征会发生复杂变化，严重影响毫米波辐射特性，甚至给检测与识别带来困难。本项目以“运动”为核心，从机理层面开展隐身飞行器毫米波辐射特性研究，重点从隐身飞行器的运动热效应出发，研究物理温度对隐身涂层毫米波辐射的影响机制，建立运动状态下隐身涂层毫米波辐射机理模型；研究运动对尾焰毫米波辐射的作用机理；剖析隐身飞行器毫米波辐射极化特性和空间分布特性与运动状态的内在关系；开展仿真和等效实测实验验证相关理论。本项目可为反隐身探测实际应用中目标信息获取和特征识别奠定理论基础，还能为未来的毫米波辐射隐身设计提供依据。

隐身飞行器的隐身涂层以及高温尾焰是其毫米波辐射的主要来源。运动状态下，隐身飞行器隐身涂层的温度分布、电磁参数以及尾焰的流场参数均会发生变化，进而对隐身飞行器的毫米波辐射特性产生影响。因此，本项目从以下三个方面开展了研究：①结合热传递理论，分析了运动状态下隐身涂层剖面的物理温度分布；建立了电磁参数的温变模型，研究了隐身涂层电磁参数随温度的变化规律；结合飞行器固有要素及观测要素，分析了各要素间的相互作用关系以及各要素对涂层毫米波辐射的影响；建立了基于运动速度的隐身涂层毫米波辐射计算模型，并进行了涂层的等效温变亮温测量实验。②建立了基于运动速度的飞行器尾焰温度场、浓度场及尺寸分布；针对典型飞行器的尾焰组分，结合尾焰的流场及尺寸分布，建立了尾焰的毫米波辐射计算模型，并通过实验验证了模型准确性。③分析了运动参数对隐身飞行器表面物理温度的影响；结合隐身涂层的毫米波辐射研究结果和隐身飞行器的复杂外形结构，计算了隐身飞行器毫米波辐射亮温并研究了运动速度和飞行姿态对毫米波辐射极化特性（线极化特性和全极化特性）和空间分布特性（不同观测方向和距离）的影响规律。