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提出了一种用于高功率微波武器的等离子体通道天线(PCA)，计算了该天线的辐射方向图。推导出了一般性天线的辐射方向函数；建立了PCA的近似电磁模型；给出了圆坐标系下PCA和周围空气中的电磁场，利用边界条件得出了PCA的色散方程，求出PCA的表面波波矢。重点讨论了PCA的辐射场随等离子体密度、天线长度、半径的变化，证实了PCA方向图的可控性。

Numerical calculation of radiation pattern of plasma channel antenna

The idea of plasma channel antenna (PCA) for high power microwave weapon is presented in this paper. The radiation pattern of PCA is calculated. The directivity functions of general antenna are derived. The near electromagnetic model of PCA is created based on physical circumstances. The electromagnetic fields of PCA and surrounding air in cylindrical coordinate are given. The dispersion equation of PCA is deduced by applying the boundary conditions of electromagnetic fields. The surface wave vector of PCA is achieved. The variations of radiation characteristic with plasma density, antenna length and antenna radius are emphatically discussed. The controllability of PCA's radiation patterns is confirmed.