Effect of mutual coupling on the scattering property of finite dipole array

An interesting phenomenon observed recently is that the scattered field from a finite dipole array becomes unstable within a certain frequency band below the central frequency of the array. In order to explain the reason for this phenomenon, the mutual coupling of the linear finite dipole array is studied by analyzing the frequency dependent property of the self- and mutual-admittance of the dipoles. The moment method is employed to obtain the currents on the dipoles.