Multifunctional Angular Bandpass Filter SIW Leaky-Wave Antenna

The synthesis of broad-beam radiation patterns with increased angular rejection and bandpass filtering functionalities from a rectilinear leaky-wave antenna (LWA) is proposed. A sharpened angular filter response is obtained with shorter antennas by introducing radiation nulls adjacent to a synthesized broad beam. Moreover, exploiting the inherent dispersive properties of LWAs, aforementioned features can be combined with bandpass frequency filtering characteristics. These angular and bandpass filtering functionalities are validated with experiments performed on fabricated prototypes in a modulated substrate-integrated waveguide technology. An enhancement in the angular rejection from 1 to 2.5 dB/° is demonstrated for a 20λ
₀
-long antenna with a broad main beam covering the range [20°, 40°] at 15 GHz and with a simultaneous bandpass in the [14 GHz, 19 GHz] band.