Design and Analysis of a Novel Vivaldi Antenna With Improved Gain for Fan Motion Detection in Smart Homes Using IR-UWB Radar

The proposed antenna is an ultra-wideband Vivaldi antenna optimized for impulse-radio ultra-wideband (IR-UWB) radar applications in smart home environments. Designed to detect indoor object motion, including fan movement, the antenna demonstrates enhanced directivity by integrating five semicircular slots and a polygonal structure in the radiating element. Fabricated on a TRF-45 substrate (dielectric constant of 4.5, loss tangent of 0.0035, thickness of 1.62 mm), the antenna exhibits an impedance bandwidth of approximately 2.28 GHz and achieves a maximum gain of 9.59 dBi at 8.5 GHz. The proposed design advances indoor motion detection capabilities for smart home applications by providing a compact, high-gain, and wideband antenna solution.