Ultra-Low-Power Rectification in Passive RFID Tags at UHF Frequencies

Abstract

The commercial significance of ubiquitous chips, especially of radio frequency identification devices (RFID), and the advantages compared to other identification technologies, for e.g. the barcode, have been discussed in several papers. The passive RFID technology is mainly advanced by the increase of the operation distance and improvements regarding the operational reliability. In order to achieve these aims, the design of integrated circuits with an ultra-low power consumption and novel concepts for high-efficiency energy scavenging are an emerging task. This article deals with self-sustaining RFID devices, which use the RF power of the interrogator as an ambient power source. For high operation distances it is necessary to realize RF to DC conversion circuits, which can handle ultra-low-power levels. Thus, we present limitations and novel design approaches concerning rectification circuits at ultra-low power levels in the context of passive RFID systems at UHF frequencies.

Uhf Rectenna Using a Bowtie Antenna

“…Accordingly, in the last years some design approaches have been proposed for rectenna systems [1][2][3][4][5][6][7][8][9][10][11][12], which are devices able to convert a free propagating EM wave into Direct Current (DC) power.…”

“…In the literature some rectenna devices working in the same range of frequencies have been proposed [7][8][9][10][11]. In [7,8] a low-cost rectenna for RFID systems is presented.…”

“…In particular, in [8] a loop with a meander design is used as antenna; the measured conversion efficiency is 4.7% when the input power is 1 mW and the load is 5 kΩ. In [9] a rectifying circuit for UHF RFID tag is proposed, the measured conversion efficiency is higher than 30% when the RF input power is 0.1 mW.…”

Monopole-Based Rectenna for Microwave Energy Harvesting of Uhf Rfid Systems

“…As a consequence, the development of efficient rectifying antennas (rectennas) has become a hot research topic [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. In fact, a rectenna is a device designed to collect the energy associated to a free propagating EM wave and to transform it into Direct Current (DC) power, thus representing the key element for EM energy harvesting and wireless power transmission applications.…”

“…Recently, several rectenna devices have been proposed in the literature [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. In particular, rectennas operating in the UHF-RFID band have been proposed in [8][9][10][11][12][13].…”