## 3 Parametric Analysis  
The change in the dimensions of the antenna's design and its impact on the antenna's performance are examined through a parametric analysis. This segment depicts a detailed antenna structure analysis to attain the UWB and dual-band notch frequency features. First, to achieve the UWB frequency spectrum, the ground plane is lowered to less than a quarter of the entire ground plane. This process is carried out by simulating the design with a full ground plane, i.e., p6 = 16 mm, a length that exhibits no frequency range below \(-\)10 dB. Further, the length of p6 is reduced in a descending manner from 16, 13.6, 11.3, 8.9, 6.6, 4.2, and 1.9 mm, correspondingly, with a step of 2.35 mm. Every magnitude results in different S11 curves, as shown in Figure 6. From this figure, it can be observed that until reaching p6 = 6.6 mm, the reflection coefficient is not below \(-\)10 dB. The ground plane length of 1.9 mm shows an impedance bandwidth between 4 and 13.7 GHz. Consequently, to improve the bandwidth further in the UWB range, especially at a lower frequency, an arc shape is included at the edges of the ground plane. The optimal length of the rectangular  
Figure 4: The simulated current distribution of the UWB antenna at (**a**) 4.5 GHz, (**b**) 8.5 GHz, and (c) 12.7 GHz.  
Figure 5: The simulated current distribution of UWB band notch antenna at (**a**) 5.4 GHz, and (**b**) 7.6 GHz.  
slot (p7) on the ground plane is chosen by performing a parametric study. An initial value of p7 is chosen at 0.1 mm, and at an incremental step of 0.1 mm until reaching 0.5 mm, it varies, respectively. The value of p7 = 0.5 results in the no-frequency spectrum below \(-\)10 dB. The corresponding S11 curve is depicted in Figure 7. The optimal dimension of the rectangular slot's width is found to be 0.2 mm, providing an impedance bandwidth of 113% in the frequency range of 3.7-13.3 GHz.  
Second, inverted U-shaped slots are used to attain the frequency notching effect. The physical dimensions of these elements are realized by performing a parametric analysis. The inverted U-shaped notch is responsible for the first notch at the center frequency of 5.4 GHz. The initial dimensions of t1 and t2 are chosen to be 0.1 mm, and t3 = 6 mm. The S11 response for this configuration shows the frequency notching shifting towards the higher frequency after reaching 5.5 GHz. To attain the WLAN frequency band notch, the t1, t2, and t3 dimensions are simultaneously increased by 0.1 mm, 0.1 mm, and 1 mm, respectively. The corresponding S11 curves are depicted in Figures 8-10. It can be witnessed from the figures that the optimum physical values of the inverted U-shaped slots were found to be t1 = 0.2 mm, t2 = 0.2 mm, and t3 = 8 mm, providing notching between the frequency range of 5-5.6 GHz. Similarly, the second notch is achieved by incorporating an inverted U-shaped slot. The optimum physical dimensions of the slot are found to be t4 = 0.5 mm, t5 = 0.4 mm, and t6 = 2 mm, resulting in the frequency notch from 7.3 to 8.3 GHz, as shown in Figures 11-13.  
Figure 6: The length of the ground plane (p6) analyzed for optimal value.  
Figure 7: The width of the rectangular slot on the ground plane is varied from 0.1 mm to 0.5 mm.  
Figure 8: The parameter t1 of the inverted U-shaped slot on the feedline is varied for choosing the ideal values.  
Figure 10: The parameter t3 of the inverted U-shaped slot on the feedline is varied for choosing the ideal values.  
Figure 9: The parameter t2 of the inverted U-shaped slot on the feedline is varied for choosing the ideal values.  
Figure 11: The parameter t4 of the inverted U-shaped slot on the radiator is varied for choosing the ideal values.  
Figure 12: The parameter t5 of the inverted U-shaped slot on the radiator is varied for choosing the ideal values.  
Figure 13: The parameter t6 of the inverted U-shaped slot on the radiator is varied for choosing the ideal values.