Scattering between the UAV swarm via artificial plasma cloud

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.