Full-Wave Leaky-Wave Analysis of 1-D Periodic Corrugated Metal Surface Antennas

A full-wave leaky-wave analysis of 1-D periodically corrugated metallic surfaces with wide gaps is presented. Such wide gaps, in the order of half-wavelength, are employed in the most cited designs for corrugated metallic antenna implementation due to the high attainable gain performance. A full-wave periodic unit cell method is described and implemented on a corrugated metal surface design for the first time. The results are compared with the known matrix pencil method. The complex dispersion characteristics verify that these structures operate as leaky-wave antennas. The calculated wavenumber of the leaky mode is then used for the analytical calculation of the radiation patterns of a finite-size antenna, based on a simple array factor approach and a near-field inspection of the electric fields of the simulated unit cell. The calculated patterns are compared to those obtained from a commercial simulation software (CST Microwave Studio), exhibiting a very good agreement.