人工等离子体云团与无人机群的散射研究

      Scattering between the UAV swarm via artificial plasma cloud

      • 摘要: 电离层中释放的金属蒸气产生人工等离子体云团,其可显著改变无线电波传播。本文利用几何绕射理论(geometrical theory of diffraction, GTD)和有限元法(finite element method, FEM)相结合的方法,给出了经由天线、人工等离子云团和无人机(unmanned aerial vehicle, UAV)群组成的传播链路中信号强度计算方法。利用30~70 MHz甚高频(very high frequency, VHF) 信号研究人工等离子体云团与UAV群的复合散射特性,得出如下结论:接收功率随着信号频率增加呈下降趋势;当机群由N架UAV构成时,阵因子迭加使机群雷达散射截面(radar cross section, RCS)出现一定的起伏,同相迭加时,接收功率可比单个UAV高约20lg N dB;利用人工等离子体云团散射可实现VHF频段用于对米级尺度RCS目标进行超视距探测,有助于解决紧急情况下电离层扰动对高频探测的不利影响。

         

        Abstract: The metal vapor released in the upper atmosphere, generates an artificial plasma cloud. In this paper, the hybrid technique of the geometric theory of diffraction (GTD) and finite element method (FEM) is introduced to estimate received power as the electromagnetic wave travels through the path of transmitting antenna-plasma cloud-UAV swarm-plasma cloud-receiving antenna. From calculations result during 30−70 MHz wave, this paper concludes as follows: the received power shows a decreasing trend with radio frequencies; if the UAV swarm is composed N UAVs, the received power is about 20lgN dB higher than that of a single UAV; the UAV swarm could be detected over-the-horizon via an artificial plasma cloud at VHF band for detecting meter-level RCS targets, which could be helpful to overcome adverse effects on HF band due to ionospheric disturbances.

         

      /

      返回文章
      返回