Design guidelines for low‐loss slow‐wave coplanar transmission lines in RF‐CMOS technology

Without changing the locations and dimensions of the patches, by changing the first dielectric layer (D1) to the one shown in Figure 5, the gain and impedance bandwidth of the antenna increases (Curve 2 of Fig. 4). In the new structure there are three dielectric layers (D11, D12, and D13) between the ground plane and the feed patch. D11 and D13 are made from the same material with the related permittivity of 2.33, and they are separated by an air gap (D12). The measured VSWR, gain, and radiation pattern of the antenna are shown in Figures 6 and 7. The measured impedance bandwidth of the antenna is 9 GHz centered at 14.5 GHz, and the VSWR is less than 1.5 from 10.5 GHz to 18 GHz which is quite useful for industrial applications. The simulation and measurement results show that the radiation pattern of the antenna is stable across the band pass. 3. CONCLUSION This letter presents a multilayer multiresonator probe-feed MSA at the frequency range of 10 –19 GHz. The antenna structure consists of a rectangular feed patch and three parasitic patches. The presented structure demonstrates that by using parasitic patches and utilizing an air gap between the feed patch and the ground plane, the gain and impedance bandwidth of the antenna increases. Finally, a high gain antenna with 62% impedance bandwidth (VSWR 2) is obtained. ACKNOWLEDGMENTS

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