Studies On Plasma Stealth Technique Application In Parts Of Plane

Plasma stealth is among the most important ways to realizing the stealth of plane. This paper focuses on the stealthy application of closed and high-frequency discharge plasma in parts of plane such as fire control radar antenna and inlet. We have carried out some exploring investigations by numerical calculations and experimental supports.Based on the stealth of mechanical scanning radar antenna in L-X wave bands, an ellipsoidal plasma cavity was designed. Firstly, the desired plasma parameters were calculated by WKB method. Secondly, the evolutionary processes of the radar antenna stealth by ellipsoidal plasma cavity were studied using finite-difference-time-domain (FDTD) method, as well as its stealthy characteristics. A voluminous ellipsoidal cavity with the material of glass fibre reinforced plastic was fabricated. Using the annular electrode to couple high-power radioheating source, the plasma was generated by ionizing Ar in cavity with low air pressure. Its stealth characteristic was also verified. From the results obtained, there is a close agreement between simulation and measurement. The pre-calculated results are appropriate to foresee the absorbed wave band by plasma. It was proved that the plasma can be used in radar antenna stealth under some condition.Based on the stealth of phasic control array radar antenna, a flat-roofed plasma cavity was designed. The evolutionary processes of the radar antenna stealth by flat-roofed plasma cavity were studied using FDTD method, as well as its stealth characteristic.Based on the stealth of inlet in the wave band of 1 GHz-2GHz, a sleevelike plasma was designed. From the simulated physical process of inlet plasma stealth using the FDTD method, the propagation path of electromagnetic waves in the cavity was achieved to clarify the complex spatio-temporal variation of electromagnetic waves in cavity. To produce a plasma layer covering the inner surface of a metal cavity, a certain number of standard commercial fluorescent lamps were placed directly against one another. Electromagnetic scattering of EM wave were studied experimentally and theoretically for metal cavity and plasma-covered metal cavity. The absorption of EM wave with covered plasma was proved to be significant. The single way attenuation is 10dB. It is first verified the feasible of plasma in inlet stealth for L-band waves.These research results will provide the theoretical and experimental reference to plasma stealth. It is feasible to apply the plasma stealthy technology in parts of plane.