We present preliminary results from the experimental investigation of the response of the atmosphere due to the impact of powerful shock waves. The response is evidenced as ultra low frequency electromagnetic wave rad...We present preliminary results from the experimental investigation of the response of the atmosphere due to the impact of powerful shock waves. The response is evidenced as ultra low frequency electromagnetic wave radiation at frequency of 2-5 kHz and in duration of 3 7s. We hypothesize that this radiation appears due to the following process： the shock wave ionizes the neutral particles in the air and these charged and neutral particles continue their vertical motion, which forms in the trail of the shock wave. Such motion can cause the cyclotron-like radiation measured.展开更多
The magnetic field distribution of an emission antenna is studied in this paper.When the slenderness ratio of the emission antenna is high,the emission antenna can be simplified as a magnetic dipole for practical appl...The magnetic field distribution of an emission antenna is studied in this paper.When the slenderness ratio of the emission antenna is high,the emission antenna can be simplified as a magnetic dipole for practical application.The numerical results of the magnetic dipole magnetic field show that the magnetic magnitude distribution has a hump-shape,whose direction is perpendicular with the antenna axis direction.A localization method based on the hump-shape signal detection is presented.The experimental result shows that the precision can reach a value of±5 cm.The method can be used to localize a pipeline robot working in a metal pipe.展开更多
文摘We present preliminary results from the experimental investigation of the response of the atmosphere due to the impact of powerful shock waves. The response is evidenced as ultra low frequency electromagnetic wave radiation at frequency of 2-5 kHz and in duration of 3 7s. We hypothesize that this radiation appears due to the following process： the shock wave ionizes the neutral particles in the air and these charged and neutral particles continue their vertical motion, which forms in the trail of the shock wave. Such motion can cause the cyclotron-like radiation measured.
基金This work was supported by the Hi-Tech Research and Development Program of China(Grant No.2001AA602021).
文摘The magnetic field distribution of an emission antenna is studied in this paper.When the slenderness ratio of the emission antenna is high,the emission antenna can be simplified as a magnetic dipole for practical application.The numerical results of the magnetic dipole magnetic field show that the magnetic magnitude distribution has a hump-shape,whose direction is perpendicular with the antenna axis direction.A localization method based on the hump-shape signal detection is presented.The experimental result shows that the precision can reach a value of±5 cm.The method can be used to localize a pipeline robot working in a metal pipe.
