Academia.eduAcademia.edu

Figure from:An Electrical Model to U-Slot Patch Antenna with Circular Polarization

See full PDFdownloadDownload figure
Table 1

Table 1

Related Figures (11)

The formula of Cgy, is used to determine the capacity C and to determine the inductance L we use the following >quations:
The formula of Cgy, is used to determine the capacity C and to determine the inductance L we use the following >quations:
Fig. 2. Design for U-slot Patch Antenna (a): without the slot, (b): with the slot
Fig. 2. Design for U-slot Patch Antenna (a): without the slot, (b): with the slot
Fig. 3. Simulated return loss of square patch antenna with varieties value of (t) Characteristics of the proposed patch antenna were simulated in this section using the CST software. The simulated curves of return loss as a function of the frequency by varying the section "t" of the proposed antenna are shown in figure3. It is noted that the proposed antenna with t = 5 mm gives the best return loss to the antenna desired frequency. Therefore, we fixed t = 5mm and cut a U-shaped slot in the radiating element of the proposed antenna to observe the variations of the return loss. The simulated results are presented in figure4. From this figure it is easy to notice that the desired frequency at 2.45GHz of the proposed antenna is obtained by the slotted structure.
Fig. 3. Simulated return loss of square patch antenna with varieties value of (t) Characteristics of the proposed patch antenna were simulated in this section using the CST software. The simulated curves of return loss as a function of the frequency by varying the section "t" of the proposed antenna are shown in figure3. It is noted that the proposed antenna with t = 5 mm gives the best return loss to the antenna desired frequency. Therefore, we fixed t = 5mm and cut a U-shaped slot in the radiating element of the proposed antenna to observe the variations of the return loss. The simulated results are presented in figure4. From this figure it is easy to notice that the desired frequency at 2.45GHz of the proposed antenna is obtained by the slotted structure.
Fig. 4. Simulated return loss for the proposed antenna with and without the slot (with CST)
Fig. 4. Simulated return loss for the proposed antenna with and without the slot (with CST)
Fig. 5. Simulated return loss for the proposed antenna
Fig. 5. Simulated return loss for the proposed antenna
Figure 6 shows the axial ratio as a function of the frequency. We chose the criterion RA < 3 dB to measure the bandwidth. Note that the bandwidth is also very low. In effect, its value is only 0.30%. This low value comes from the use of truncated corners. Sharma [1] showed that this type of antenna could not provide a large bandwidth at the axial ratio. Fig. 6. Simulated axial ratio for the proposed antenna
Figure 6 shows the axial ratio as a function of the frequency. We chose the criterion RA < 3 dB to measure the bandwidth. Note that the bandwidth is also very low. In effect, its value is only 0.30%. This low value comes from the use of truncated corners. Sharma [1] showed that this type of antenna could not provide a large bandwidth at the axial ratio. Fig. 6. Simulated axial ratio for the proposed antenna
The linear and nonlinear gain of theta / phi 0° in polar form are represented respectively by figure 8.
The linear and nonlinear gain of theta / phi 0° in polar form are represented respectively by figure 8.
Fig. 8. The polar pattern: (a) Linear and (b) Non-linear Fig. 7. 3D Farfield for U-slot antenna
Fig. 8. The polar pattern: (a) Linear and (b) Non-linear Fig. 7. 3D Farfield for U-slot antenna
Fig.9. Surface current at U-slot Patch Antenna, (a): LHCP and (b): RHCP antenna can work with truncated LHCP at another diagona axis.
Fig.9. Surface current at U-slot Patch Antenna, (a): LHCP and (b): RHCP antenna can work with truncated LHCP at another diagona axis.