Design of a Simple Low-cost Rectenna for Low Power RFID Wireless Power Transmission Applications Md. Abdullah-Al-Mamun 1 , Rajib Sarker 2 , Jahirul Hoque 3 Rezaul Karim Mazumder 4 Dept. of Electronics & Telecommunication Engineering, University of Liberal Arts Bangladesh 123 , Dept. of AP. Electronics & Communication Engineering, University of Dhaka 4 ABSTRACT Numerous tiny portable devices like RFID (Radio Frequency Identification Device) are operated without batteries [1][2]. In certain RFID application, a fixed output DC current and voltage is needed to activate this device. The RECTENNA (RECtifying anTENNA) is a receiving arrangement combined with an antenna and a rectifying circuit which converts RF or microwave power into useful DC power. In this paper an effort has been taken to develop low-cost Rectenna circuits at 915MHz (RFID band) for low power applications usable in many tiny grain size electronic devices. We have designed a single diode rectifier and a doubler circuit to compare their performance for maximum efficiencies and reject higher order harmonics. For both the circuits commercial surface mount Zero Bias small signal Schottky detector diodes of Agilent HSMS-285B [2] at frequencies below 1.5GHz are used. Study of the performance indicates that, DC output voltage of the doubler rectifier circuit produces 0.85V at a DC load of 1700Ω, whereas a single diode rectifier generates 0.50V at a DC load of 800Ω when the input RF power is 0dBm. It is also seen that at the same input power the highest conversion efficiency from the doubler is 85%, when the efficiency of the single diode rectifier is 50%. This study shows clearly that doubler rectifier produces higher efficiency power generation. INTRODUCTION A rectenna which is composed of receiving antennas and rectification circuit plays an important role in free space wireless power transmission (WPT) that efficiently converts radio frequency (RF) energy into useful direct current (DC) power. It can be operated under both large and small signal (low power) conditions. In some low power RFID applications, the rectenna is required to supply certain DC output current and voltage to activate a tiny Integrated Circuit (IC). In small signal condition (≤ 0 dBm), the efficiency is quite low since the diode is not fully operated in the forward bias condition and because of power dissipation in the diode. This paper compares the operation of the doubler voltage rectifier circuit with a single diode rectifier circuit at 915MHz as shown in Fig.2(a) and (b). 1 Corresponding author: cell: +8801613019490 email: mamun19871987@gmail.com