Abstract
A highly efficient and compact quad-band energy harvester (QBEH) circuit based on the extended composite right- and left-handed transmission lines (E-CRLH TLs) technique is presented. The design procedure based on E-CRLH TLs at four desired frequency bands is introduced to realize a quad-band matching network. The proposed QBEH operates at four frequency bands: <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">${{{\bf f}}_1} = 0.75\,{{\bf GHz}};\,{{{\bf f}}_2} = 1.8\,{{\bf GHz}};\,{{{\bf f}}_3} = 2.4\,{{\bf GHz}}$</tex-math></inline-formula> ; and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">${{{\bf f}}_4} = 5.8\,{{\bf GHz}}$</tex-math></inline-formula> . The simulations and experimental results of the proposed QBEH exhibit overall (end to end) efficiency of 55% and 70% while excited at four frequency bands simultaneously with <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ - 20\,{{\bf dBm}}$</tex-math></inline-formula> (10 μW) and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ - 10\,{{\bf dBm}}$</tex-math></inline-formula> (100 μW) input power, respectively. Due to applying multitone excitation technique and radio frequency (RF) combining method in the QBEH circuit, the sensitivity is improved, and sufficient power is generated to realize a self-sustainable sensor ( <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">S</i> <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> ) using ambient low-level RF signals. A favorable impedance matching over a broad low input power range of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ - $</tex-math></inline-formula> 50 to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$ - $</tex-math></inline-formula> 10 dBm (0.01 to 100 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">μ</i> W) is achieved, enabling the proposed QBEH to harvest ambient RF energy in urban environments. Moreover, an accurate theoretical analyses based on the Volterra series and Laplace transformation are presented to maximize the output dc current of the rectifier over a wide input power range. Theoretical, simulation and measurement results are in excellent agreement, which validate the design accuracy for the proposed quad-band structure. The proposed new energy harvesting technique has the potential to practically realize a green energy harvesting solution to generate a viable energy source for low-powered sensors and IoT devices, anytime, anywhere.
Highlights
T HE INTERNET of Things (IoTs) is spawning the use of sensors, which are both pervasive and ubiquitous in every aspect of our lives
A new technique was presented to realize a compact quad-band energy harvester (QBEH) circuit based on the extended composite right/lefthanded (E-CRLH) transmission line (TL)
The proposed QBEH exhibits a broad matching over a low input power range of −50 to −10 dBm (0.01 to 100 μW) which makes it a suitable candidate for EM energy harvesting in urban environments
Summary
T HE INTERNET of Things (IoTs) is spawning the use of sensors, which are both pervasive and ubiquitous in every aspect of our lives. Enabling simultaneous multiband and multitone signals in the input of an EH and taking the advantage of RF combining method, the rectification device can be turned on at low input power levels available in ambient, the rectifier sensitivity can be improved, resulting in enhanced output dc power, provided that the system can operate over a broad input power range and at different frequency bands [19], [20]. The parallel branches are not capable of capturing low-level ambient RF signals, this solution is not suitable for ambient RF energy scavenging Another approach to design a multiband EH is using a wideband antenna and a multiband matching network to enhance RF combining at the input of the rectifier circuit [26]–[28].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
