Printed Metasurface Leaky Wave Antennas Based on Penetrable Aperture Field Synthesis

A design methodology for 1-D modulated printed metasurface leaky wave antennas (LWAs) with a pattern synthesis capability in 2-D TE polarization is presented. For a desired radiation pattern, complete tangential fields on the surface of a grounded dielectric substrate are constructed and optimized to find a pointwise passive surface impedance distribution. Dielectric and conductor losses are considered in the field synthesis process via a design curve obtained using analysis of a physical unit cell with lossy constituents. It enables accurate prediction of the aperture field distribution when practical lossy materials are used. A spatially modulated impedance can be realized using an array of printed copper strips. Three 10-wavelength-long LWA designs are demonstrated numerically for broadside, two-beam, and sector patterns. The LWA for broadside radiation is fabricated and measured, showing a good agreement with the simulation results.