Left-handed leaky wave antenna for millimeter-wave applications

In this paper, we have designed microstrip left-handed leaky wave antennas (LH LWAs) working from 75 to 82 GHz, and we have conformed beam scanning by MoM simulation. A conventional LH LWA for microwave applications consists of series interdigital capacitors and shunt stubs connected with vias to the ground. Manufacturing the interdigital capacitor and meander-line inductor working at mm-wave frequencies is very hard because of the etching tolerance. In the case of the mm-wave antenna, the value of capacitance, and inductance becomes smaller than that of the microwave antenna, so the interdigital capacitor and shunt meander-line inductor can be replaced with a simple gap capacitor and line inductor. In this paper, we have designed a planar mm-wave frequency LH LWA. In order to maximize the fabrication tolerance, we have chosen a via-free LH structure with a simple series gap and a straight shunt inductor connected with a virtual ground patch in the unit cell, which will contribute to reducing conductor losses as well.