A Physically Compact Coplanar Waveguide (CPW)-fed Flexible Antenna for mmWave 5G Applications

A compact and flexible coplanar waveguide (CPW) fed antenna with physical dimensions of 10 $\times$ 6mm
²
and electrical size of 0.35$\lambda \times$ 0.21$\lambda$ is presented herein. The antenna was inkjet printed with silver nanoparticles ink on a Polyethylene Terephthalate (PET) substrate that has a thickness of 0.135 mm, loss tangent of 0.002, and a dielectric permittivity of 3.2. The antenna was experimentally tested on a Vector Network Analyzer (VNA) under flat and bent conditions. The observed results are in good agreement with the simulated results indicating an operational frequency range between 10.50 and 31.75 GHz, covering the upper X, Ku, K, and the lower Ka bands. The antenna resonates at 26.1 GHz and exhibits greater performance in the lower Ka band with simulated radiation efficiency over 84% and an average gain of 5 dBi. The fractional bandwidth of the antenna was found to be 100.6%. This reported compact ultrawideband flexible antenna has the potential to be employed in wireless communication systems, wireless portable devices, smart consumer electronics, and wearables.