Analysis and Design of Planar Surface Wave Lenses and Application to Leaky-Wave Antennas

Planar metasurface lens structures based on microstrip technology, optimized to control the propagation of surface waves (SWs), are presented. Two different lenses are studied, i.e., a converging or plane-wave-like lens and a diverging lens. Near-field simulations and measurements are reported to demonstrate the guiding features of the designed lenses, which have also been proposed as a feeding system for planar leaky-wave antennas (LWAs). Far-field results show improvements in terms of reduced cross polarization and sidelobe level as well as increased realized gain when compared without these SW lenses. The proposed structures are also simple to manufacture and are employed herein to control SW fields generated by a TM0 surface-wave launcher (SWL) integrated in the ground plane of the developed prototype demonstrators. Some applications include high-gain radar and remote sensing satellite antennas as well as microwave and millimeter-wave communication systems.