Radio frequency energy harvesting using circular spiral inductor antenna

The design of radio frequency (RF) energy harvesting using planar circular spiral inductor antenna is proposed. The purpose is to determine the feasibility to harvest power density produced by the proposed antenna. A single element circular spiral antenna was designed, and subsequently, a 2 × 1 array to enhance the gain. Being a circular spiral inductor, it has a good Q-factor, higher inductance per unit area, and compact capability. The entire structure was investigated using numerical solver such as finite integration technique (FIT) method and Agilent advance design system (ADS) software. Results show that 3.22 dBi gain for single antenna and 5.14 dBi gain for antenna array was achieved at a centre frequency of 520 MHz. The gain of the 2 × 1 antenna array increased to about 37.3% over the single element. There are noticed reasonable agreements between the simulated and measured result.