A topical design of circularly polarized fractal boundary antenna for RF harvesting

Abstract

In this paper, a fractal boundary with circularly polarized (CP) antennas has been introduced for Radio Frequency (RF) harvesting. RF energy can be captured from the atmosphere with the help of circularly polarized antenna and this may be transformed to DC energy by means of impedance matching network and rectifying circuit. The suggested antennas have been designed by cutting symmetric rectangular slot on diagonal axis & at the boundary with triangular slot at flare angles of 45degree, 60 degrees of the opposite side to get CP. Optimization of indentation depth has been done for getting good result. The simulated and tested results of antenna are in better compatibility. Any Microstrip antenna will work as a CP, when the axial ratio value is less than 3dB. The suggested antennas have achieved axial ratio value of about 1.72dB. Another advantage of proposed antenna over physical size is about 0.25l 0 × 0.25l 0 × 0.012l 0. In comparison with antenna size, proposed antenna requires less area. The fulfillment of antenna among all parameters is commendable and it can also be used for RF energy harvesting.