Magnetic antenna for improving penetrability of electromagnetic wave in plasma

Abstract

The invention belongs to a magnetic antenna for high-speed aircraft navigation and communication, which comprises a columnar spiral antenna, a closed antenna cover, a strong magnet ground plate and a conical coaxial feeding wire column. In the magnetic antenna, the spiral antenna of an axial mode is adopted, the antenna and a strong permanent magnet are integrated, the magnet serves as a magnetic field generator to generate a high permanent field and also serves as the antenna ground plate, when magnetic field intensity B is more than or equal to 0.5T, signal emitted by the spiral antenna can effectively penetrate a plasma, when the magnetic field of the permanent magnet is increased to 1.0T, antenna gain is increased to 9.6dB and approaches 10.6dB of the antenna gain in air, and the attenuation of electromagnetic wave during transmission in the plasma is reduced by 30dB. Therefore, the magnetic antenna has the characteristics of frequency bandwidth, circular polarization bandwidth, low attenuation amplitude of the electromagnetic wave of the antenna and the like, the antenna gain and the penetrability of the plasma are effectively improved, and the defect of communication interrupt caused by the existence of a surface plasma sheath in a background technology is overcome.

Description

technical field [0001] The invention belongs to a magnet antenna for navigation and communication of high-speed aircraft, in particular to a three-dimensional helical antenna for plasma sheaths on the surface of the aircraft. The attenuation of the electromagnetic wave radiated by the antenna in the plasma can be greatly reduced, thereby overcoming the communication interruption problem between the aircraft and the ground caused by the plasma sheath on the surface of the aircraft. Background technique [0002] When the aircraft flies through the atmosphere at hypersonic speed, the high-temperature gas around the aircraft will be partially ionized to form plasma. During the propagation of electromagnetic waves through the plasma sheath, due to reflection, refraction and absorption by the plasma sheath, the energy will be greatly attenuated, and even the transmission will be completely interrupted. At present, the main measures to reduce the attenuation of electromagnetic wav...

AI Technical Summary

Problems solved by technology

This is because the Q value of the microstrip antenna is very high, and the S11 bandwidth is relatively narrow, and the circular polarization can be satisfied at a certain frequency point by using the angle-cutting method, but the circular polarization bandwidth is not too wide, and the gain of the microstrip antenna is generally small , unable to meet the high-gain requirements of the antenna of the penetrating plasma microwave communication system

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