An Inkjet-Printed UWB-MIMO Antenna with Band Rejection Capability for Wireless Network Applications

In this paper, a Coplanar Waveguide (CPW) fed monopole antenna for Ultra-wideband Multiple-Input-Multiple-Output (UWB-MIMO) having band rejection capability at Wimax/WLAN is presented. Band rejection characteristic is achieved by introducing an inverted U-slot in the bevel shaped monopole radiating patch. The proposed design is printed on a low cost and flexible PET plastic substrate using silver nanoparticle ink. The unit cell design has a compact size of 18 × 18 × 0.145 mm3. It offers −10 dB return loss bandwidth from (3.8 GHz–12 GHz) with band rejection at the IEEE WLAN and Wimax standard bands. Similarly, the 4x4 MIMO differentially fed antenna with orthogonal dual polarized feed maintains the compact size and band rejection capability with dimensions of 40 × 40 × 0.145 mm3. The MIMO antenna demonstrates reflection coefficient less than −10 dB from (3.7 GHz–11.1 GHz). High isolation below −15 dB is observed among the ports. Other important MIMO parameters such as envelop correlation and diversity gain are analyzed and compared. The results achieved make the proposed antenna configurations viable candidates for integration among wireless network devices and applications that utilize the UWB spectrum.