A study of planar leaky-wave antenna designs fed by practical surface-wave launchers

In the typical analysis of high gain leaky-wave antennas (LWAs) studies are generally limited to pattern directivity, gain, and calculations of the complex wavenumber. These studies are very important to ensure efficient antenna design but little attention is generally given to other important engineering aspects. For instance, one challenging problem when practically implementing planar LWAs at microwave and millimeter-wave frequencies is the inclusion of an efficient feeding scheme. Recent studies by the authors have shown that surface-wave launchers (SWLs) can be a practical and efficient feeding technique for such planar LWAs where energy can couple into the dominant surface-wave (SW) mode of the slab. In this work we analyze and consider two planar LWA designs fed by such printed SWLs. The SW and radiated powers are derived in comparison to the input power as a function of frequency as well as the complex wavenumbers.