Synthesis Procedure for Thinned Leaky-Wave-Based Arrays With Reduced Number of Elements

F. Scattone (1) , M. Ettorre (1) , Benjamin Fuchs (1) , R. Sauleau (1) , N. J. G Fonseca

1 IETR - Institut d'Électronique et des Technologies du numéRique

We proposed a synthesis method to design thinned leaky-wave-based arrays. The array elements are small waveguide apertures opened on a ground plane. A superstrate (impedance sheet, dielectric slab, etc.) is placed above the array. The array elements excite leaky-wave modes between the ground plane and the superstrate, enhancing the aperture efficiency of the final antenna. An iterative optimization procedure based on a convex l1 minimization is used to reduce the number of array elements, maintaining the radiated field within a predefined mask. All the embedded element patterns are evaluated for each source through a fast Green's function spectral approach, taking into account the effects of the mutual coupling during the optimization procedure. The use of a superstrate provides array structures with a reduced number of elements and enhanced aperture efficiency with respect to configurations without superstrate. The level of the grating lobes is also controlled during the optimization. A parametric study is performed to understand the capabilities of the leaky-wave-thinned array varying the reflectivity of the superstrate. As an example, an array of 18 elements working over a 7% fractional bandwidth is synthesized, providing a reduction by a factor of 4 in the number of elements when compared to a configuration with the same requirements, but without superstrate

Keywords: Antenna arrays; antenna radiation patterns; Apertures; array elements; convex minimization; embedded element patterns; fast Green function spectral approach; grating lobes; Gratings; ground plane; iterative methods; iterative optimization procedure; leaky wave antennas; Leaky-wave antennas; Leaky-wave antennas (LWAs); leaky-wave modes; leaky-wave-thinned array; minimisation; Minimization; mutual coupling; Optimization; radiated field; reduced number of elements; thinned array antennas; thinned leaky-wave-based arrays; waveguide antenna arrays; waveguide apertures

Domains: Engineering Sciences [physics]; Electronics; Computer Science [cs]; Networking and Internet Architecture [cs.NI]

F. Scattone, M. Ettorre, Benjamin Fuchs, R. Sauleau, N. J. G Fonseca. Synthesis Procedure for Thinned Leaky-Wave-Based Arrays With Reduced Number of Elements. IEEE Transactions on Antennas and Propagation, 2016, 64 (2), pp.582--590. ⟨10.1109/TAP.2015.2509008⟩. ⟨hal-01300881⟩