5.2 Franklin monopole antenna

Part C of the multiband rectenna system is a Franklin strip monopole dual-band antenna to be used to cover Bluetooth at 2.4 GHz, 4G, LTE bands at 2.3, 2.5 and 2.6 GHz, WiMAX at 2.5 and 5.5GHz, WLAN at 2.4, 5.2 GHz [53]. The geometry of the antenna is shown in Figure 29. The antenna has a rectangular stub on a curved partial ground. The length of the bending strip is about one-half of the guide wavelength at its first resonance frequency. The meander radius and the length of the Franklin strip are mainly determining the two resonance frequencies of the antenna, while the rectangular stub with a length of a quarter wavelength and curved ground have been used to increase the bandwidth of the upper band (5.5 GHz). The L-C equivalent circuit of the Franklin monopole antenna is shown in Figure 30. The dimensions of the antenna are shown in Table 7, while the equivalent circuit parameters are shown in Table 8.
