Analysis on Radiation Characteristic of Plasma Channel Antenna in a Finite Magnetic Field

In order to cover the shortage of the antennas for high power microwave weapon currently, the idea of plas- ma channel antenna （PCA） is presented. The radiation characteristic of PCA is researched. Based on its operation princi- ple, the PCA is equivalent to uniform cold magnetized plasma beam, which is assumed to be gyrating transversely and drifting longitudinally. The cross-section of the plasma beam is considered as a circle and the shape is invariant along with axis. The directivity functions of generalized antenna are derived. The dispersion equation of PCA is deduced from Maxwell~ equations and constitutive relations. The surface wave vector of PCA is achieved. The variations of radiation characteristic with plasma density, antenna length, antenna radius and longitudinal velocity are emphatically discussed. Some useful conclusions are obtained, which gives a solid foundation for practical application of the idea. Key words： PCA（ Plasma Channel Antenna） , Finite magnetic field, Radiation characteristic。