A microstrip periodic leaky-wave antenna optimized for broadside scanning

In this paper a microstrip periodic leaky-wave antenna optimized for radiation scanning through broadside is presented. This antenna is based on the excitation of a leaky mode that propagates along the structure, with radiation occurring from the -1 space harmonic. The specific geometry of the metalization inside the unit cell permits a continuous scanning from the backward to the forward quadrant without any degradation of the beam, avoiding the presence of open-stopband effects. This new design provides a valid alternative to metamaterial leaky-wave antennas already presented in the literature and demonstrates the possibility of obtaining a conventional microstrip periodic LWA operating in the -1 harmonic with a backfire-to-endfire frequency-scanning capability.