A Novel Long Slot Air-Filled Substrate Integrated Waveguide Fixed-Beam Leaky-Wave Antenna

A new leaky-wave antenna based on air-filled substrate integrated waveguide (SIW) with fixed-beam performance is proposed in this paper. On the top face of SIW, a long gap is etched as radiator. The design can radiate at a fixed angle within a wide band, since the electromagnetic waves can travel in the air in the form of fast wave. The simulated results reveals that the relative bandwidth of the proposed design operates more than 28.6% from 12-16 GHz frequency range and the measured main beam deviation is 60° with only varies ±2°. Besides, the simulated maximal gain is from 13.8 to 16 dBi, while the measured peak gain reaches up to 15.3 dBi during the working frequency range.