## 3 Results and Analysis  
In this study, an orthogonally configured array antenna has been simulated on the roof of a vehicle. To achieve high polarization efficiency, the E and H plane pattern performance of the proposed antenna must track in both amplitude and phase over the required FOV. The cross-polarized response shows that the polarization efficiency is inversely proportional to the unwanted energy. The simulation results are calculated using the High Frequency Structure Simulator (HFSS). Figure 3 shows the simulated near-field radiation of the proposed WAVE antenna. \begin{table}
\begin{tabular}{c c} \hline \hline
**Characteristic** & **Parameter** \\ \hline Base Material & Teflon \\ Permititivity [ \(\varepsilon\) ] & 2.2 \\ Thickness & 0.8 mm \\ Width & 9.6 mm \\ Length & 169 mm \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Characteristics of the proposed wireless access for vehicular environment antenna structure. Figure 1: Proposed antenna structure. Figure 2: Structure of the proposed antenna model with a ground layer and a feed layer. The FOV requirements differ for WAVE communication systems. Further, it is essential for the return loss of the WAVE communication systems to exhibit a minimum value of -24.47 dB over the FOV. The FOV for WAVE communication systems is elevated at an angle of 15\({}^{\circ}\) above the edge to center. However, only an omnidirectional FOV is required by consumers. Figure 4 shows the simulated return loss of the proposed WAVE antenna. The simulation results show that the proposed array antenna model improves the return loss from -24.47 dB to -19.70 dB. Figure 5 shows the simulation result for the voltage standing wave ratio (VSWR) for WAVE communication systems. As shown in this figure, the array antenna model exhibits a sufficient VSWR of 1.18 for the WAVE bandwidth. Figure 4: Simulation result of return loss. Figure 3: Simulation result of near-field radiation. Figure 6 shows the proposed vehicular WAVE antenna. This antenna comprises a WAVE band patch antenna, microwave printed circuit substrates, discrete RF components, a ceramic patch for the GPS satellite, and digital audio broadcasting (DAB). From the results of the measurement, it can be inferred that in most cases, the simulated results are not in good agreement with the results obtained with the vehicular antenna, despite the fact that the same vehicular antenna meets the same specifications on a ground plane in an anechoic chamber. During a special test drive, the performance of the proposed antenna has been evaluated by placing the antenna on different points on the roof of a vehicle. Figure 7 shows the measured return loss of the proposed WAVE antenna. Figure 5: Simulation result of voltage standing wave ratio (VSWR). Figure 6: Proposed vehicular antennas model with GPS and DAB. From the results of the measurement, it is found that the array antenna model has a VSWR of 1.44 for the WAVE bandwidth, as shown in Figure 8.  
Figures 9 and 10 show the radiation beam patterns of the antenna vertically located on the roof of a vehicle. The proposed array antenna exhibits a gain of up to 3 dB over the FOV, as compared with a shark fin type omnidirectional antenna model. From the results of the simulation and measurement of the implemented prototype models, the radiation pattern of the WAVE array patch antenna is analyzed for an actual vehicle. The far-field radiation pattern of the proposed antenna was analyzed in two different ways to compare the results of the ground test with those of the anechoic chamber test. Figure 8: Measurement result of VSWR. Figure 7: Measurement result of return loss. The analytical solution of the array in space shows a gain of 7 dBi for the radiation component. This reference value is used to analyze the following high-frequency structure simulation systems. The results of the measurement analysis show that the surface current is distributed on the metallic parts of the vehicle body. The intensity of this current is expressed in terms of the azimuth and elevation angles.