ELECTRICALLY SMALL ACS-FED FLIPPED MIMO ANTENNA FOR USB PORTABLE APPLICATIONS

An electrically small Asymmetric Co-planar Strip (ACS)-fed MIMO antenna for USB wireless applications is proposed. MIMO antenna consists of two electrically small antennas inserted inside a 3D-printed USB prototype. Electrically small ACS-fed antenna consists of an F-shaped monopole radiator with a U-shaped slot inserted into it. The proposed antenna is compact with dimensions 11 X 20 X 0.508 [mm.sup.3]. The proposed MIMO antenna has dual bands which caters to WiMAX-3.5/5.5 GHz, WLAN-5.8GHz, and C-band-6.3 GHz. The proposed architecture attains reasonable gain for the available aperture. Also, ACS-fed antenna achieves fractional bandwidth of 22% and 20% in the lower and upper bands respectively complying with the theoretical bandwidth as defined by Chu's limit. Isolation between the radiators is greater than 15 dB in both the operating bands. Radiation patterns have high integrity, and actual USB deployment is presented. Simulation and measurement results are presented.