Compact Base Station Antenna Based on Image Theory for UWB/5G RTLS Embraced Smart Parking of Driverless Cars

The Internet of Thing (IoT) and fifth-generation mobile communication networks (5G) are leading towards a paradigm shift by proving seamless connectivity to a large number of devices. The applications of IoT in smart cities have further attracted local authorities to adopt technologies such as driverless cars, smart parking and smart waste management. This paper presents a compact base station antenna design with enhanced directivity/gain for ultra-wideband (UWB)/5G embraced real-time location systems (RTLS) based smart parking of driverless cars. The proposed base station antenna is based on image theory to achieve enhanced directivity and narrower beam width without using more array elements to keep smaller dimensions. Moreover, the base station antenna consists of an antipodal dipole printed on the opposite side of Rogers 4350 substrate, and a metal plate carefully designed and placed to produce a mirror image in order to achieve a high value of directivity in a specified direction. The advantage behind the antipodal dipole configuration is to avoid the use of extra balun for impedance matching. The half-power beamwidth of 110° is achieved along with 7 dB gain by placing a reflector plane at the distance of 0.25~\lambda \text{o} from the proposed antipodal dipole antenna. Also, this antenna provides a bandwidth ranging from 6 to 7.25 GHz, which can be used for UWB or 5G based RTLS systems. Furthermore, the proposed compact antenna design will help to improve the localization accuracy of ultra- wideband RTLS systems for smart parking applications of autonomous cars.