Suppression of reflected wave of leaky-wave antenna by utilizing an aperture-fed patch antenna

Here, we present a method to suppress the back lobe of a short leaky-wave antenna by using an aperture-fed patch antenna on the backside. The aperture-fed patch antenna is connected to the open end of the leaky-wave antenna (LWA). Such a design offers another radiation path of the reflected wave and creates another radiation pattern on the back plane of the substrate. Experimental results show that the suppression of the reflected wave can be 10 dB at 10.0 GHz with an LWA length of 6 cm (2 wavelengths). The suppression bandwidth is 200 MHz owing to the narrow bandwidths of the aperture and patch. Compared to conventional designs, this novel structure can radiate as efficiently as an LWA with a length of 4 wavelengths. The two radiation patterns on the different planes have great potential in many applications and provide more flexibility than traditional designs.