基于STAP的机载气象雷达低空风切变检测方法研究

发布时间：2018-06-07 10:07

本文选题：机载气象雷达 + 相控阵　；参考：《中国民航大学》2015年硕士论文

【摘要】：低空风切变具有尺度小、强度大、不易检测等特点,是飞机在起飞和降落阶段严重的安全隐患。机载气象雷达是飞机感知前方气象信息的有力工具,当雷达前视检测低空风切变时,有用信号淹没在地杂波背景中,使得低空风切变的检测变得困难。国外研究表明,相控阵天线以其灵活度高、扫描速度快、易于波束赋形的特点成为现代雷达的重要发展方向,新一代机载气象雷达将采用相控阵体制,拥有更强的地杂波抑制能力,可以更好地在地杂波背景中检测危险气象信息。针对新体制机载气象雷达,研究基于空时自适应处理(Space Time Adaptive Processing,STAP)的低空风切变检测方法是航空安全领域的一个重要课题。首先,论文介绍了机载前视阵几何模型和该模型下的空时二维杂波模型,在介绍低空风切变建模方法的基础上,研究了风场回波模型,并分别对机载前视阵条件下的地杂波与低空风切变信号进行了仿真与分析。其次,论文介绍了传统的风切变检测流程,并对风速估计和风速梯度估计模块的经典方法进行了比较与分析。再次,针对相控阵体制的机载气象雷达,论文提出了基于广义CAPON的低空风切变风速估计方法。该方法结合低空风切变信号的分布式目标特点构建基于广义CAPON的空时处理器,可有效地抑制地杂波并精确估计风场风速。最后,论文在广义CAPON算法的基础上,提出了基于??-STAP的低空风切变风速估计方法。该方法将??-STAP原理应用于低空风切变风速估计中,可进一步降低算法运算复杂度。仿真实验证明了该方法的有效性。
[Abstract]:Low-altitude wind shear has the characteristics of small scale, high intensity and difficult to detect. It is a serious safety hazard for aircraft in take-off and landing stages. Airborne weather radar is a powerful tool for aircraft to perceive the meteorological information in front. When radar looks forward to detect low-altitude wind shear, useful signals are submerged in the background of ground clutter, which makes detection of low-altitude wind shear difficult. Foreign studies show that phased array antenna is an important development direction of modern radar because of its high flexibility, high scanning speed and easy beamforming. The new generation airborne meteorological radar will adopt phased array system. It has stronger ground clutter suppression ability and can detect dangerous weather information better in ground clutter background. For the new airborne weather radar, it is an important subject in aviation safety field to study the low-altitude wind shear detection method based on space-time adaptive processing space Time Adaptive processing phase. Firstly, the geometric model of airborne foresight array and the space-time two-dimensional clutter model based on this model are introduced. Based on the introduction of low-altitude wind shear modeling method, the wind echo model is studied. The ground clutter and low level wind shear signals are simulated and analyzed respectively under the condition of airborne forward view array. Secondly, the traditional flow of wind shear detection is introduced, and the classical methods of wind speed estimation and wind speed gradient estimation are compared and analyzed. Thirdly, for airborne meteorological radar with phased array system, a method of wind shear wind speed estimation at low altitude based on generalized CAPON is proposed in this paper. Combined with the distributed target characteristics of low-altitude wind shear signals, this method constructs a space-time processor based on generalized CAPON, which can effectively suppress ground clutter and accurately estimate wind velocity. Finally, based on the generalized CAPON algorithm, a method of wind shear wind speed estimation at low altitude based on STAP is proposed. In this method, the principle of STAP is applied to wind shear wind speed estimation at low altitude, which can further reduce the computational complexity of the algorithm. The simulation results show that the method is effective.
【学位授予单位】：中国民航大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN959.4

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