Bandwidth Manipulated Leaky-Wave Antenna using a Sinusoidal Ridge in Folded Substrate Integrated Waveguide

The impedance bandwidth for leaky-wave antennas (LWAs) is usually very broad, leading to wide signal interference from unwanted spectrums. For instance, the uplink signals will cause jamming effect to the downlink for Satellite communication systems. Hence, an integrated LWA with a bandpass filter is proposed in this paper. A folded substrate integrated waveguide (FSIW) LWA is utilized to reduce the SIW width to build a 2D LWA array with low side lobes. Periodic fan-shaped slots are etched on the top of the FSIW for circular polarization in a band centered at 11.5 GHz. A bandpass filter is investigated by elaborating a sinusoidal ridge in the FSIW LWA. It has been successfully validated through full-wave simulation that the bandpass filtering can be manipulated by varying the amplitude of the sine curve, whereas the circular polarization is well maintained. The proposed antenna is a very promising candidate for next-generation satellite communication systems.