Figure 9 Variation of simulated and measured VSWR with respect to frequency
BROADBAND GAIN AND RADIATION EFFICIENCY
Figure 10 (a) shows the variation of antenna gain for the operational band from 4.395-10.184 GHz. Antenna gain quantifies the maximum distance that can be covered by the electromagnetic (EM) wave. The proposed fractal MPA array shows a maximum gain of 3.84 dB at 8.9 GHz frequency (simulated) and 3.81 dB at 9.25 GHz frequency (measured) with an average simulated gain of ≥ 1.2 dB (for both ports).
As shown in Figure 10 (b), the radiation efficiency (ηrad) is ≥ 74% (simulated) throughout the UWB of operation. The proposed fractal array radiates with a maximum efficiency of 88.8% at 6.2 GHz frequency.