Mutual coupling characteristics of two unbalanced fed ultra low profile inverted L antennas closely faced each other

The WPT system composed of the unbalanced fed, ultra low profile inverted L antenna on a rectangular conducting plane is proposed and analyzed numerically. The input impedances of transmitting and receiving antennas are matched to 50 ohms by adjusting the length of horizontal element and the feed point position. The size of conducting plane is 550 mm by 1,283 mm. The antenna height h is 70 mm (wavelength/43). In the case of the distance between transmitting and receiving antennas is 140 mm, the power transfer efficiency becomes 92.2% at the design frequency of 100 MHz.