A Novel Energy Harvester for Powering Small UAVs: Performance Analysis, Model Validation and Flight Results

The proposed work aims at exploring and developing new strategies to extend mission parameters (measured as travel distance and mission duration (MD)) of a new class of unmanned vehicles, named Micro Air Vehicles (MAVs). In this paper, a new analytical model, identifying all factors, which determine the MAV power consumption, is presented. Starting from the new model, the design of a nanoarray energy harvester, based on plasmonics nano-antenna technology is proposed. The preliminary study was based on a 22,066,058 22,066,058 × 62,800-dipole rectenna array producing an output power level of 84.14 mW, and an energy value of 2572 J under a power density of 100 mW/cm² and a resonant frequency of 350 THz as input conditions. The preliminary analytical results show a possible recharge of an ultra-fast rechargeable battery on board of a MAV and an MD improvement of 16.30 min.

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Autonomous Energy Harvester Based on Textile-Based Enzymatic Biofuel Cell for On-Demand Usage

Sensors ◽

10.3390/s20175009 ◽

2020 ◽

Vol 20 (17) ◽

pp. 5009

Author(s):

Seonho Seok ◽

Cong Wang ◽

Elie Lefeuvre ◽

Jungyul Park

Keyword(s):

Power Management ◽

Output Power ◽

Output Voltage ◽

Energy Harvester ◽

Power Level ◽

Biofuel Cell ◽

Output Power Level ◽

Crystal Oscillator ◽

On Demand ◽

Enzymatic Biofuel Cell

This paper presents an autonomous energy harvester based on a textile-based enzymatic biofuel cell, enabling an efficient power management and on-demand usage. The proposed biofuel cell works by an enzymatic reaction with glucose in sweat absorbed by the specially designed textile for sustainable and efficient energy harvesting. The output power of the textile-based biofuel cell has been optimized by changing electrode size and stacking electrodes and corresponding fluidic channels suitable for following power management circuit. The output power level of single electrode is estimated less than 0.5 μW and thus a two-staged power management circuit using intermediate supercapacitor has been presented. As a solution to produce a higher power level, multiple stacks of biofuel cell electrodes have been proposed and thus the textile-based biofuel cell employing serially connected 5 stacks produces a maximal power of 13 μW with an output voltage of 0.88 V when load resistance is 40 kΩ. A buck-boost converter employing a crystal oscillator directly triggered by DC output voltage of the biofuel cell makes it possible to obtain output voltage of the DC–DC converter is 6.75 V. The efficiency of the DC–DC converter is estimated as approximately 50% when the output power of the biofuel cell is tens microwatts. In addition, LT-spice modeling and simulation has been presented to estimate power consumption of each element of the proposed DC–DC converter circuit and the predicted output voltage has good agreement with measurement result.

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Pump Laser Automatic Signal Control for Erbium-Doped Fiber Amplifier Gain, Noise Figure, and Output Spectral Power

Journal of Optical Communications ◽

10.1515/joc-2019-0203 ◽

2019 ◽

Vol 0 (0) ◽

Author(s):

I. S. Amiri ◽

Ahmed Nabih Zaki Rashed ◽

P. Yupapin

Keyword(s):

Noise Figure ◽

Spectral Power ◽

Power Level ◽

Fiber Amplifier ◽

Pump Laser ◽

Output Power Level ◽

Signal Control ◽

Erbium Doped Fiber Amplifier ◽

Erbium Doped ◽

Amplifier Gain

AbstractThis paper has simulated the pump laser automatic signal control for erbium-doped fiber amplifier gain, noise figure, and output spectral power. Signal gain and noise figure are deeply studied in relation to laser pump power variations at operating pumping wavelengths of 980 nm and 1,480 nm for previous and proposed models. Similar to the study of the light signal to noise ratio, output power level and maximum Q factor are also simulated versus EDFA amplifier length at pumping power of 500 mW and different pumping wavelength by using the proposed model. The obtained results are better by using a pumping wavelength of 1,480 nm than a pumping wavelength of 980 nm. The optimum EDFA amplifier is 5 m, which gives better performance than other amplifier lengths.

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Facile and Promising Method for Michael Addition of Indole and Pyrrole to Electron-Deficienttrans-β-Nitroolefins Catalyzed by a Hydrogen Bond Donor Catalyst Feist’s Acid and Preliminary Study of Antimicrobial Activity

The Scientific World JOURNAL ◽

10.1155/2014/649197 ◽

2014 ◽

Vol 2014 ◽

pp. 1-15 ◽

Cited By ~ 4

Author(s):

Abdullah M. A. Al Majid ◽

Mohammad Shahidul Islam ◽

Assem Barakat ◽

Mohamed H. M. Al-Agamy ◽

Mu. Naushad

Keyword(s):

Antimicrobial Activity ◽

Hydrogen Bond ◽

Michael Addition ◽

Hydrogen Bond Donor ◽

New Class ◽

Optimum Reaction ◽

Preliminary Study ◽

Cooperative Hydrogen Bonding ◽

The Michael Addition

The importance of cooperative hydrogen-bonding effects has been demonstrated using novel 3-methylenecyclopropane-1,2-dicarboxylic acid (Feist’s acid (FA)) as hydrogen bond donor catalysts for the addition of indole and pyrrole totrans-β-nitrostyrene derivatives. Because of the hydrogen bond donor (HBD) ability, Feist’s acid (FA) has been introduced as a new class of hydrogen bond donor catalysts for the activation of nitroolefin towards nucleophilic substitution reaction. It has effectively catalyzed the Michael addition of indoles and pyrrole toβ-nitroolefins under optimum reaction condition to furnish the corresponding Michael adducts in good to excellent yields (up to 98%). The method is general, atom-economical, convenient, and eco-friendly and could provide excellent yields and regioselectivities. Some newly synthesized compounds were for examinedin vitroantimicrobial activity and their preliminary results are reported.

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Microdrilled tapers to enhance optical fiber lasers for sensing

Scientific Reports ◽

10.1038/s41598-021-00046-7 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

R. A. Perez-Herrera ◽

M. Bravo ◽

P. Roldan-Varona ◽

D. Leandro ◽

L. Rodriguez-Cobo ◽

...

Keyword(s):

Optical Fiber ◽

Optical Fibers ◽

Fiber Lasers ◽

Signal To Noise Ratio ◽

Power Level ◽

Single Mode ◽

Optical Signal ◽

Single Mode Fiber ◽

Output Power Level ◽

Linear Cavity

AbstractIn this work, an experimental analysis of the performance of different types of quasi-randomly distributed reflectors inscribed into a single-mode fiber as a sensing mirror is presented. These artificially-controlled backscattering fiber reflectors are used in short linear cavity fiber lasers. In particular, laser emission and sensor application features are analyzed when employing optical tapered fibers, micro-drilled optical fibers and 50 μm-waist or 100 μm-waist micro-drilled tapered fibers (MDTF). Single-wavelength laser with an output power level of about 8.2 dBm and an optical signal-to-noise ratio of 45 dB were measured when employing a 50 μm-waist micro-drilled tapered optical fiber. The achieved temperature sensitivities were similar to those of FBGs; however, the strain sensitivity improved more than one order of magnitude in comparison with FBG sensors, attaining slope sensitivities as good as 18.1 pm/με when using a 50 μm-waist MDTF as distributed reflector.

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A 350-GHz Coupled Stack Oscillator with −0.8 dBm Output Power in 65-nm Bulk CMOS Process

Electronics ◽

10.3390/electronics9081214 ◽

2020 ◽

Vol 9 (8) ◽

pp. 1214

Author(s):

Thanh Dat Nguyen ◽

Jong-Phil Hong

Keyword(s):

Output Power ◽

Supply Voltage ◽

Second Harmonic ◽

Power Level ◽

Cmos Technology ◽

Negative Resistance ◽

Output Power Level ◽

Cmos Process ◽

Frequency Selective ◽

Oscillation Frequencies

This paper presents a push-push coupled stack oscillator that achieves a high output power level at terahertz (THz) wave frequency. The proposed stack oscillator core adopts a frequency selective negative resistance topology to improve negative transconductance at the fundamental frequency and a transformer connected between gate and drain terminals of cross pair transistors to minimize the power loss at the second harmonic frequency. Next, the phases and the oscillation frequencies between the oscillator cores are locked by employing an inductor of frequency selective negative resistance topology. The proposed topology was implemented in a 65-nm bulk CMOS technology. The highest measured output power is −0.8 dBm at 353.2 GHz while dissipating 205 mW from a 2.8 V supply voltage.

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An Analysis Model Combining Gamma-Type Stirling Engine and Power Converter

Energies ◽

10.3390/en12071322 ◽

2019 ◽

Vol 12 (7) ◽

pp. 1322 ◽

Cited By ~ 1

Author(s):

Hua-Ju Shih

Keyword(s):

Low Temperature ◽

Bias Voltage ◽

Temperature Difference ◽

Energy Harvester ◽

Waste Heat ◽

Power Converter ◽

Stirling Engine ◽

Living Environment ◽

Analysis Model ◽

Variable Capacitance

Waste heat is a potential source for powering our living environment. It can be harvested and transformed into electricity. Ohmic heat is a common type of waste heat. However, waste heat has the following limitations: wide distribution, insufficient temperature difference (ΔT < 70 K) for triggering turbines, and producing voltage below the open voltage of the battery. This paper proposes an energy harvester model that combines a gamma-type Stirling engine and variable capacitance. The energy harvester model is different from Tavakolpour-Saleh’s free-piston-type engine [7.1 W at ΔT = 407 K (273–680 K)]. The gamma-type Stirling engine is a low-temperature-difference engine. It can be triggered by a minimum ΔT value of 12 K (293–305 K). The triggering force in the variable capacitance is almost zero. Furthermore, the gamma-type Stirling engine is suitable for harvesting waste heat at room temperature. This study indicates that 21 mW of energy can be produced at ΔT = 30 K (293–323 K) for a bias voltage of 70 V and volume of 103.25 cc. Because of the given bias voltage, the energy harvester can break through the open voltage of the battery to achieve energy storage at a low temperature difference.

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Efficient Implementation of Multichannel FM and T-DMB Repeater in FPGA with Automatic Gain Controller

Electronics ◽

10.3390/electronics8050482 ◽

2019 ◽

Vol 8 (5) ◽

pp. 482

Author(s):

Mangi Han ◽

Youngmin Kim

Keyword(s):

High Performance ◽

Electronic Device ◽

Finite Impulse Response ◽

Parallel Implementation ◽

Power Level ◽

Digital Signal ◽

Digital Circuit ◽

Output Power Level ◽

Verilog Hdl ◽

Field Programmable

In this study, we implemented a high-performance multichannel repeater, both for FM and T-Digital Multimedia Broadcasting (DMB) signals using a Field Programmable Gate Array (FPGA). In a system for providing services using wireless communication, a radio-shaded area is inevitably generated due to various obstacles. Thus, an electronic device that receives weak or low-level signals and retransmits them at a higher level is crucial. In addition, parallel implementation of digital filters and gain controllers is necessary for a multichannel repeater. When power level is too low or too high, the repeater is required to compensate the power level and ensure a stable signal. However, analog- and software-based repeaters are expensive and they are difficult to install. They also cannot effectively process multichannel in parallel. The proposed system exploits various digital signal-processing algorithms, which include modulation, demodulation, Cascaded Integrator Comb (CIC) filters, Finite Impulse Response (FIR) filters, Interpolated Second Ordered Polynomials (ISOP) filters, and Automatic Gain Controllers (AGCs). The newly proposed AGC is more efficient than others in terms of computation amount and throughput. The designed digital circuit was implemented by using Verilog HDL, and tested using a Xilinx Kintex 7 device. As a result, the proposed repeater can simultaneously handle 40 FM channels and 6 DMB channels in parallel. Output power level is also always maintained by the AGC.

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