Synthesis of broad-beam patterns through leaky-wave antennas with rectilinear geometry

The feasibility of broad-beam radiation-pattern synthesis through leaky-wave antennas (LWAs) with rectilinear geometry is shown for the first time. The synthesis is based on a geometrical-optics approach and is achieved by a nonstandard tapering of a straight LWA, which involves the variation of both phase and leakage constants of leaky-mode propagating along the structure. Such an approach is an alternative to that based on a curved LWA and allows for a simpler manufacturing and a significant bulk reduction of the structure. The relevant theory is provided together with examples of broad-beam pattern synthesis.