Tham khảo tài liệu 'microstrip antennas part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Analysis into Proximity-Coupled Microstrip Antenna on Dielectric Lens 169 wavelength in the lens at 38 GHz is mm. Our selection of hemisphere s radius as 50 mm is quite good for the requirement that the lens radius is much larger than the wavelength. According to 3-11 extension length has to be mm. Figure 5-2 shows the theoretical and measured return loss of the proximity-coupled lens antenna. The measurements were performed using a Wiltron 360B 40 GHz Vector Network Analyzer. As can be seen from these results good agreement between theory and experiment was achieved. The predicted and measured 10 dB return loss bandwidths are and respectively. Fig. 5-2 Predicted and measured return loss curves The predicted and measured E-plane and H-plane copolar radiation patterns at 38 GHz are shown in Figure 5-3 and 5-4 respectively. Once again good agreement between theory and experiment is evident from these plots particularly in the main lobes. Results and discussion Figure 5-2 shows the predicted and measured return loss of the proximity-coupled lens antenna. The measurements were done using a Wiltron 360B 40 GHz Vector Network Analyzer. As can be seen from these results good agreement between theory and experiment was achieved. A high degree of precision is required in the manufacture to achieve such a good match between measured and simulated results. The predicted and measured 10 dB return loss bandwidths are and respectively. The slight shift in resonant frequency of can be attributed to uncertainties in the dielectric properties of the materials Agr or even slight misalignment of the layers. The predicted and measured E-plane and H-plane co-polar radiation patterns at 38 GHz are shown in Figure 5-3 and 5-4 respectively. Once again good agreement between theory and experiment is evident from these plots particularly in the main lobes. The slight discrepancy in the sidelobe level is due to total internal reflection in the .
