动力论法修正高功率微波大气传输的大气介电常数

Modification of the dielectric constant of atmosphere for high power microwave propagation with dynamic method

高功率微波在大气中传输会使气体电离产生等离子体,导致大气的介电常数和折射指数发生变化。介绍了在初等理论条件下各向同性的等离子体中的大气介电常数,给出速度为麦克斯韦分布时电子与分子的碰撞对介电常数的影响,并用动力论法导出高功率微波作用下的大气介电常数及修正系数公式。

When a high power microwave pulse propagates through the atmosphere, the ionization is expected to occur and produces plasma, and dielectric constant and refractive index of air will change. This paper introduces the dielectric constant of isotropy plasma in primary theory. It presents the influence of collision frequency between electron and gas molecule on the dielectric constant of air based on Maxwell's distribution of velocity. The air dielectric constant in high power microwave propagation in atmosphere and its correction coefficient are introduced by the method of dynamics. The correction of coefficient relate to the frequency and collision frequency. When the ratio of them is very big, the correction of coefficient approximate 1, when the ration of them is small, it approximate 1.5.