# A Low-Profile Dual-Polarized Magneto-Electric Dipole Antenna for 5G Applications
## 2 Materials and Methods
### Parametric Analysis  
The working principle and structural advantages of the proposed MED were introduced above. The electric dipole structure adopted the common square patch structure, and the metal floor structure adopted the fence structure, which is described in detail here. This part focuses on the influence of parameter dimensions on the proposed MED performance. Antenna models with different parameter dimensions were modeled and simulated by HFSS; then, the influence of parameter dimensions on the proposed MED performance was analyzed, and finally the optimal parameter dimensions were compared and selected from the simulation results.  
The simulation results of different parameter dimensions are shown in Figure 5. As we can see, the length of the electric dipole affected the second resonance at around 4.3 GHz, with an increase in the length, the resonance and the peak gain moved to a lower frequency, the reflection coefficients became better, but the working bandwidth became narrower. In order to balance the performance of the MED, a suitable length le = 24 mm was chosen.  
Figure 4(b) shows that the height of the magnetic dipole affected the first resonance at around 3.5 GHz. With an increase in the height, the resonance moved to a lower frequency, the working bandwidth became wider, but the reflection coefficients became worse. In order to balance the performance of the MED, a suitable length hm = 13 mm was chosen. The influence of the length of the magnetic dipole is shown in Figure 4(c). As we can see, as the length of the magnetic dipole increased, both of the two resonances and gain peaks moved to lower frequencies. Therefore, the appropriate magnetic dipole length should be selected according to the set center frequency, i.e., 3.8 GHz.  
Figure 4: Current distributions on the metal wall (**a**) without slots and (**b**) with slots.  
Figure 5d depicts the effect of the height of the feeding structure, as we analyzed earlier. The height of the feeding structure was mainly designed to adjust the impedance matching with the horizontal structure of the feeding source, i.e., it showed an effect on the reflection coefficients, and had basically no effect on the gain.  
Figure 5e,f introduce the effect of meandering slots length and height on MED performance. We can see that the effect of both is similar to that of magnetic dipole height, i.e., it mainly affects the first resonance point. This is consistent with our previous analysis that the main effect of meandering slots is to extend the current path and lower the MED profile, which is equivalent to changing the magnetic dipole height.  
In addition to the above-mentioned parameter dimensions, other parameter dimensions also have an impact on the MED performance, such as the floor size (lg), the width of the feed structure (d), etc., whose analysis process is not be introduced due to the length of this study. Through the analysis of parameters and comprehensive consideration of the performance of various MEDs, the final parameter dimensions were selected and listed in Table 1.