Parasitic antenna with interdigital structure for TV broadcast energy harvesting

This paper presents a novel parasitic antenna for RF energy harvesting. The antenna consists of a planar driven dipole and a planar parasitic dipole which are printed on the bottom and top surfaces of a substrate, respectively. For each dipole, meander lines are used for size reduction and transferring the RF power. Moreover, by loading these two dipoles with interdigital structures, the antenna impedance and the radiation directivity can be tuned. A slot-modified reflector is also applied for the purpose of unifying the current direction and improving the radiation directivity and efficiency. The measured -10dB bandwidth is from 508 to 521MHz and the simulated peak gain is 3.26dBi at 515MHz. A rectifier based on HSMS2862 diode is presented. The proposed antenna is employed by the rectifier the received dc voltage is up to 536 mV. The proposed antenna has advantages such as high efficiency, high directivity and electrically small structure, which is suitable for energy harvesting in TV broadcast bands.