Novel compensation method for electromagnetic performance of dielectric radome based on reflector shaping

From the viewpoint of geometrical optics, dielectric radome degrades the electromagnetic performance of the enclosed antenna by distorting the amplitude distribution and phase distribution of aperture field, of which the latter is mainly responsible for the distortion of far-field pattern. A novel method based on reflector shaping is proposed to compensate the phase distortion of aperture field caused by radome. The aperture field of the shaped reflector antenna possesses a phase distribution, which has an inverse trend when compared with the phase distortion caused by radome, thus making the aperture field become equiphase after transmitting through the radome. Two different antenna-radome systems are simulated and the results show that the proposed method is effective, particularly for compensating the distortion of far-field pattern such as the variation of sidelobe and null depth. Further analysis indicates that the shaping method is applicable to multifrequency-band antenna-radome systems.