Design and Analysis of Quad Dumbbell Shaped Directive UWB Antenna for Microwave Tumour Detection Integrated with Meander Strip Resonators

Abstract

A novel design of a dumbbell shape quad elliptical slotted (DSQES) antenna for directive ultra-wideband (UWB) integrated with WCDMA, WLAN, and mid-band of 5G applications is presented. Initially, a circular patch is designed by inserting four elliptical slots in radiator with a rectangular slotted ground plane. To realize ultra-wide impedance bandwidth, three symmetrical stepped rectangular slots are inserted in ground below a stepped-quarter-wave-transformer feed line. The proposed antenna achieves fractional bandwidth (FBW) of 104% (S11 < −10 dB) which covers UWB frequency range of 5.4-17.3 GHz at resonant frequencies 5.8/7.4/10.3/12/15.7 GHz. Further, a ground structure is customized by loading two asymmetrical meander strip resonators (MSRs), which provides extra lower frequency bands 2.1 GHz (1.96-2.21 GHz) and 3.5 GHz (3.22-4.07 GHz) for WCDMA, WLAN, and 5G mid-band applications, respectively. Furthermore, the measured gain and half-power-beam-width (HPBW) are 1.7-6.4 dBi and 75 • -20 • in 5.4-17.3 GHz UWB, respectively. The optimized dimension of proposed antenna is 30 × 30 mm 2 which is simulated on Computer Simulation Technology (CST) electromagnetic simulator using an FR-4 substrate of thickness 1.6 mm and dielectric constant 4.3. The simulated structure is computed by ADS simulator, and simulated results are validated with measured ones.