George Shaker

An ambient electromagnetic energy harvesting system for on-body
sensors is presented. Specifically, a smart contact lens that monitors the
glucose level in the tear fluid of a user is demonstrated. The energy
harvesting system rectifies a portion of a cell phone/smartphone-emitted
uplink signal into DC power for the operations of on-lens sensors and
components. An actual cow eye is used to assist in various
measurements of the proposed energy harvester. Ultimately, a power… Show more

An ambient electromagnetic energy harvesting system for on-body
sensors is presented. Specifically, a smart contact lens that monitors the
glucose level in the tear fluid of a user is demonstrated. The energy
harvesting system rectifies a portion of a cell phone/smartphone-emitted
uplink signal into DC power for the operations of on-lens sensors and
components. An actual cow eye is used to assist in various
measurements of the proposed energy harvester. Ultimately, a power of
1mW at about 1V is harvested and delivered to a resistive load of
2KOhm when a cell phone is held in a typical reading position. This
harvested power level is more than adequate to enable numerous
possible on-body sensors.
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In this paper, inkjet-printed flexible sensors fabricated on paper substrates are introduced as a system-level solution for ultra-low-cost mass production of UHF Radio Frequency Identification (RFID) Tags and wireless sensor nodes in a “green” approach that could be easily extended to other microwave and wireless applications. The authors briefly touch up the state-of-the-art area of fully integrated wireless sensor modules on paper and show several active and power scavenging platforms to… Show more

In this paper, inkjet-printed flexible sensors fabricated on paper substrates are introduced as a system-level solution for ultra-low-cost mass production of UHF Radio Frequency Identification (RFID) Tags and wireless sensor nodes in a “green” approach that could be easily extended to other microwave and wireless applications. The authors briefly touch up the state-of-the-art area of fully integrated wireless sensor modules on paper and show several active and power scavenging platforms to power on wireless sensors that could potentially set the foundation for the truly convergent wireless sensor ad hoc networks of the future. Show less

For the first time, we demonstrate the feasibility of realizing ultra-wideband
antennas through ink-jetting of conductive inks on commercially available paper sheets. The
characterization of the conductive ink as well as of the electrical properties of the paper
substrate is reported for frequencies up to 10GHz. This work is one step further towards the
development of low-cost environment-friendly conformal printed antennas/electronics for ad-
hoc wireless sensor networks… Show more

For the first time, we demonstrate the feasibility of realizing ultra-wideband
antennas through ink-jetting of conductive inks on commercially available paper sheets. The
characterization of the conductive ink as well as of the electrical properties of the paper
substrate is reported for frequencies up to 10GHz. This work is one step further towards the
development of low-cost environment-friendly conformal printed antennas/electronics for ad-
hoc wireless sensor networks operating in rugged environments. Show less

This paper realizes the low-cost mm-Wave antennas using inkjet printing of silver nano-particles. It is widely spread that fabrication of mm-Wave antennas and microwave circuits using the typical (deposit/pattern/etch) scheme is a challenging and costly process, due to the strict limitations on permissible tolerances. Such fabrication technique becomes even more challenging when dealing with flexible substrate materials, such as liquid crystal polymers. On the other hand, inkjet printing of… Show more

This paper realizes the low-cost mm-Wave antennas using inkjet printing of silver nano-particles. It is widely spread that fabrication of mm-Wave antennas and microwave circuits using the typical (deposit/pattern/etch) scheme is a challenging and costly process, due to the strict limitations on permissible tolerances. Such fabrication technique becomes even more challenging when dealing with flexible substrate materials, such as liquid crystal polymers. On the other hand, inkjet printing of conductive inks managed to form an emerging fabrication technology that has gained lots of attention over the last few years. Such process allows the deposition of conductive particles directly at the desired location on a substrate of interest, without need for mask productions, alignments, or etching. This means the inkjet printing of conductive materials could present the future of environment-friendly low-cost rapid manufacturing of RF circuits and antennas. Show less

In this paper, the fabrication and characterization of newly developed photonic crystal (PC) polarization-controlling devices on a silicon-on-insulator wafer for integrated terahertz applications are presented. The polarization converter is composed of periodic asymmetric loaded PC slab waveguide. Square- and circular-hole PC slab waveguides were studied using a 3-D finite-difference time-domain method. For a square-hole PC-based polarization rotator, polarization rotation efficiency higher… Show more

In this paper, the fabrication and characterization of newly developed photonic crystal (PC) polarization-controlling devices on a silicon-on-insulator wafer for integrated terahertz applications are presented. The polarization converter is composed of periodic asymmetric loaded PC slab waveguide. Square- and circular-hole PC slab waveguides were studied using a 3-D finite-difference time-domain method. For a square-hole PC-based polarization rotator, polarization rotation efficiency higher than 90% was achieved within the normalized frequency band of a/ λ = 0.258-0.267 . In circular-hole PC polarization converter, the polarization conversion efficiency dropped to 70% for the aforementioned frequency band. Low polarization conversion efficiency of the circular-hole PC-based device is attributed to scattering loss at the top loaded layers. Thus, the square-hole PC structure is a better candidate for integrated terahertz polarization-controlling devices. Planar terahertz integrated circuit technology was developed to implement the proposed device. Characterization setup was designed using rigorous numerical methods to use the newly introduced Agilent Millimeter-wave PNA-X network analyzer (up to 500 GHz) as a source. Scattering parameter characterizations provide a good measure of polarization extinction ratio. For the devices designed for the central frequency of f = 200 GHz, it was observed that, within the frequency band of 198-208 GHz (α/λ = 0.26-0.272), the ratio of S21 to S11 was higher than 15 dB. The bandwidth is in good agreement with our preliminary design presented before. Show less

One of 5 Invited talks in the BioMedical Stream.