The power consumption of a variable optical attenuator（VOA） array based on a silica planar lightwave circuit was investigated. The thermal field profile of the device was optimized using the finite-element analysis....The power consumption of a variable optical attenuator（VOA） array based on a silica planar lightwave circuit was investigated. The thermal field profile of the device was optimized using the finite-element analysis. The simulation results showed that the power consumption reduces as the depth of the heat-insulating grooves is deeper, the up-cladding is thinner,the down-cladding is thicker, and the width of the cladding ridge is narrower. The materials component and thickness of the electrodes were also optimized to guarantee the driving voltage under 5 V. The power consumption was successfully reduced to as low as 155 mW at an attenuation of 30 dB in the experiment.展开更多
We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. Fo...We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.展开更多
A new method of prefetching data blocks from the NVCache to the page cache in main memory and cascading prefetching n-blocks from a hard disk to the NVCache together was proposed to reduce the spin-up frequency of a h...A new method of prefetching data blocks from the NVCache to the page cache in main memory and cascading prefetching n-blocks from a hard disk to the NVCache together was proposed to reduce the spin-up frequency of a hybrid hard disk drive and thus enhance I/O performance.The proposed method consists of three steps:1) Analyzing the pattern of read requests in block units;2) Determining the number of blocks prefetched to the NVCache;3) Replacing blocks in the NVCache according to the block replacement policy.The proposed method can reduce the latency time of a hybrid hard disk and optimize the power consumption of an IPTV set-top box.Experimental results show that the proposed method provides better average response time compared to an existing adaptive multistream prefetching(AMP) method by 25.17%.It also reduces by 20.83% the average power consumption over that of the existing external caching in energy saving storage system(EXCES) method.展开更多
A model of enhancement mode GaAs MESFET (EFET) for low power consumption and low noise applications has been obtained by using a small signal equivalent circuit whose component values are derived from the physical p...A model of enhancement mode GaAs MESFET (EFET) for low power consumption and low noise applications has been obtained by using a small signal equivalent circuit whose component values are derived from the physical parameters and the bias condition. The dependence of the RF performance and DC power consumption on physical, material and technological parameters of EFET is also studied. The optimum range of the physical parameters is given which is useful for the design of active device of ultra low power consumption MMIC.展开更多
Health monitoring with wearable pulse oximetry(PO)paves the way for personalized,point-of-care health management.Organic PO(OPO)sensors are particularly promising for wearable POs due to their excellent compatibility ...Health monitoring with wearable pulse oximetry(PO)paves the way for personalized,point-of-care health management.Organic PO(OPO)sensors are particularly promising for wearable POs due to their excellent compatibility with flexible,lightweight form factors and design freedom,enabling low power consumption comparable to or even surpassing that of conventional inorganic systems.However,further power reductions are crucial for wearable systems with limited onboard power,and achieving sufficient signal strength at minimal luminance is essential for extended operation.Here,we propose an OPO structure with both ultralow power consumption and low luminance operation.By combining a ring-shaped,vertically stacked two-color organic light-emitting diode(OLED)with a circular organic photodiode(OPD)filling the interior and exterior of the OLED ring,we demonstrate OPO sensors requiring only a fewμW to drive the OLEDs and operable at a few tens of cd/m^(2),demonstrating potentials for continuous health monitoring with extended long-term operation.展开更多
A highly sensitive in-situ turbidity sensor with the low power consumption was proposed and evaluated in this study. To meet the practical requirements of the in-situ detection, we have designed the light scattering p...A highly sensitive in-situ turbidity sensor with the low power consumption was proposed and evaluated in this study. To meet the practical requirements of the in-situ detection, we have designed the light scattering path, watertight mechanical structure, and ultra-weak scattering light detecting method. Experiments showed that the sensor had a sensitivity of 0.0076 FTU with the concentration range of 0 - 25 FTU and the R-square of 0.9999. The sensor could withstand the water pressure in depth of 1000m and had the low power consumption in the active mode 10.4mA, sleep mode 65 pA with a supply voltage of 8.4V. Southern China Sea buoy experiments indicated that the sensor could work well in the actual in-situ environment. In comparison with sensors of other companies, our sensor had relatively more comprehensive performance.展开更多
The seafloor vector magnetometer is an effective tool for marine geomagnetic surveys and seafloor magnetotelluric(MT)detection.However,the noise,power consumption,cost,and volume characteristics of existing seafloor v...The seafloor vector magnetometer is an effective tool for marine geomagnetic surveys and seafloor magnetotelluric(MT)detection.However,the noise,power consumption,cost,and volume characteristics of existing seafloor vector magnetometers are insufficient for practical use.Therefore,a low-noise,low-power-consumption seafloor vector magnetometer that can be used for data acquisition of deep-ocean geomagnetic vector components is developed and presented.A seafloor vector magnetometer mainly consists of a fluxgate sensor,data acquisition module,acoustic release module,glass sphere,frame,burn-wire release,and anchor.A new low-noise data acquisition module and a fluxgate sensor greatly reduce power consumption.Furthermore,compact size is achieved by integrating an acoustic telemetry module and replacing the acoustic release with an external burn-wire release.The new design and magnetometer characteristics reduce the volume of the instrument and the cost of hardware considerably,thereby improving the integrity and deployment efficiency of the equipment.Theoretically,it can operate for 90 days underwater at a maximum depth of 6000 m.The seafloor vector magnetometer was tested in the South China Sea and the Philippine Sea and obtained high-quality geomagnetic data.The deep-water environment facilitates magnetic field data measurements,and the magnetometer has an approximate noise level of 10 pT/rt(Hz)@1 Hz,a peak-to-peak value error of 0.2 nT,and approximate power consumption of 200 mW.The fluxgate sensor can measure the magnetic field in the lower frequency band and realize geomagnetic field measurements over prolonged periods.展开更多
Retinal-inspired synaptic phototransistors,which integrate light signal detection,preprocessing,and memory functions,show promising applications in artificial vision sensors.In recent years,it has been reported to con...Retinal-inspired synaptic phototransistors,which integrate light signal detection,preprocessing,and memory functions,show promising applications in artificial vision sensors.In recent years,it has been reported to construct heterojunction in phototransistors to realize positive photoconductance(PPC)and negative photoconductance(NPC)modulations,thereby achieving visible and infrared wavelength discrimination and various visual functions.However,relatively little attention has been paid to wavelength-dependent switching and reconfigurability between two states(PPC and NPC),limiting further applications for complex simulations of biological visual functions.Here,a mixed organic–inorganic heterojunction synaptic phototransistor was constructed by integrating CsPbBr_(3)nanoplates(NPLs)with strong blue-light absorption and poly(3-hexylthiophene-2,5-diyl)(P3HT)with strong red-light absorption.Compared with the three-dimensional(3D)structure CsPbBr_(3)nanocubes(NCs),the two-dimensional(2D)CsPbBr_(3)NPLs exhibited more efficient charge transfer with P3HT.Based on the individual optical absorption properties in organic–inorganic heterojunction,the device exhibited wavelength-selective and reconfigurable behavior between PPC and NPC.A low power consumption of 0.053 fJ per synaptic event was achieved,which is comparable to a biological synapse.Finally,Drosophila's evasive behavior to food under red and blue light can be successfully demonstrated.This work demonstrates the future potential of synaptic phototransistors for visuomorphic computing.展开更多
A test pattern generator （TPG） which can highly reduce the peak power consumption during built-in self-test （BIST） application is proposed. The proposed TPG, called LPpe-TPG, consists of a linear feedback shift re...A test pattern generator （TPG） which can highly reduce the peak power consumption during built-in self-test （BIST） application is proposed. The proposed TPG, called LPpe-TPG, consists of a linear feedback shift register （LFSR） and some control circuits. A procedure is presented firstly to make compare vectors between pseudorandom test patterns by adding some circuits to the original LFSR and secondly to insert some vectors between two successive pseudorandom test patterns according to the ordinal selection of every two bits of the compare vector. Then the changes between any successive test patterns of the test set generated by the LPpe-TPG are not more than twice. This leads to a decrease of the weighted switching activity （WSA） of the circuit under test （CUT） and therefore a reduction of the power consumption. Experimental results based on some ISCAS＇ 85 benchmark circuits show that the peak power consumption has been reduced by 25.25% to 64.46%. Also, the effectiveness of our approach to reduce the total and average power consumption is kept, without losing stuck-at fault coverage.展开更多
Using composite field arithmetic in Galois field can result in the compact Rijndael S-Box. However, the power con- sumption of this solution is too large to be used in resource-limited embedded systems. A full-custom ...Using composite field arithmetic in Galois field can result in the compact Rijndael S-Box. However, the power con- sumption of this solution is too large to be used in resource-limited embedded systems. A full-custom hardware implementation of composite field S-Box is proposed for these targeted domains in this paper. The minimization of power consumption is implemented by optimizing the architecture of the composite field S-Box and using the pass transmission gate (PTG) to realize the logic functions of S-Box. Power simulations were performed using the netlist extracted from the layout. HSPICE simulation results indicated that the proposed S-Box achieves low power consumption of about 130 μW at 10 MHz using 0.25 μm/2.5 V technology, while the consumptions of the positive polarity reed-muller (PPRM) based S-Box and composite field S-Box based on the conventional CMOS logic style are about 240 μW and 420 μW, respectively. The simulations also showed that the presented S-Box obtains better low-voltage operating property, which is clearly relevant for applications like sensor nodes, smart cards and radio frequency identification (RFID) tags.展开更多
A study of wireless technologies for IoT applications in terms of power consumption has been presented in this paper. The study focuses on the importance of using low power wireless techniques and modules in IoT appli...A study of wireless technologies for IoT applications in terms of power consumption has been presented in this paper. The study focuses on the importance of using low power wireless techniques and modules in IoT applications by introducing a comparative between different low power wireless communication techniques such as ZigBee, Low Power Wi-Fi, 6LowPAN, LPWA and their modules to conserve power and longing the life for the IoT network sensors. The approach of the study is in term of protocol used and the particular module that achieve that protocol. The candidate protocols are classified according to the range of connectivity between sensor nodes. For short ranges connectivity the candidate protocols are ZigBee, 6LoWPAN and low power Wi-Fi. For long connectivity the candidate is LoRaWAN protocol. The results of the study demonstrate that the choice of module for each protocol plays a vital role in battery life due to the difference of power consumption for each module/protocol. So, the evaluation of protocols with each other depends on the module used.展开更多
The surge in data volume and algorithmic complexity necessitates the development of highly integrated,low-power,and high-performance electronic components.Conventional complementary metal-oxide-semiconductor(CMOS)inve...The surge in data volume and algorithmic complexity necessitates the development of highly integrated,low-power,and high-performance electronic components.Conventional complementary metal-oxide-semiconductor(CMOS)inverters,which rely solely on isotropic two-dimensional materials,encounter limitations due to their single voltage output,thereby impeding the miniaturization of integrated circuits.In this study,we introduce anisotropic CMOS inverters based on n-ReS_(2)and p-WSe_(2),which demonstrate distinct voltage transfer characteristics across various crystalline orientations.These inverters exhibit the lowest voltage gain along the a-axis of ReS_(2)flakes,whereas they possess the highest voltage gain and the lowest static power consumption along the b-axis.By optimizing the gate dielectric on substrates,the inverter achieves an enhanced voltage gain of 30.8 and an ultra-low power consumption of 5.4 pW along the b-axis direction,when fabricated on a 35 nm Al_(2)O_(3)substrate deposited via atomic layer deposition(ALD)method.Additionally,it captures a clear dynamic switching behavior at a supply voltage of 3 V under a 20 Hz square wave input signal.This study proposes a potential approach to circuit miniaturization by leveraging anisotropic two-dimensional materials for the integration of diverse voltage transfer characteristics within a single logic device,thereby achieving a combination of low power consumption and high-density integration.展开更多
There is a great demand for high-performance hydrogen sulfide(H_(2)S)sensors with low operating temperatures.Ag/In_(2)O_(3)hexagonal tubes with different proportions were prepared by the calcination of Ag+-impregnated...There is a great demand for high-performance hydrogen sulfide(H_(2)S)sensors with low operating temperatures.Ag/In_(2)O_(3)hexagonal tubes with different proportions were prepared by the calcination of Ag+-impregnated indium-organic frameworks(CPP-3(In)),and the developed sensors exhibit enhanced gas-sensing performance toward H_(2)S.Gas sensing measurements indicate that the response of Ag/In_(2)O_(3)(2.5 wt%)sensor to 5 ppm H_(2)S has the highest response(119),operated at 70℃.The Ag/In_(2)O_(3)(2.5 wt%)based sensor exhibits short response time(20 s),low detection limit(300 ppb),and good selectivity toward H_(2)S gas,which imply that the CPP-3(In)-derived Ag/In_(2)O_(3)hexagonal tube is a promising candidate to be constructed a low power-consumption H_(2)S sensor.展开更多
In this study, the green energy saving of greenhouse sensor node is de- signed to reduce the system power consumption and high efficiency. The green renewable solar energy resources are used as the energy source of no...In this study, the green energy saving of greenhouse sensor node is de- signed to reduce the system power consumption and high efficiency. The green renewable solar energy resources are used as the energy source of nodes; the lowenergy consumed and cost effective MSP430 chip is used as the main control chip of the processor unit; the transmission frequency of the wireless transmission unit is 433 MHz, which has the characteristics of low power consumption, high signal strength, long transmission distance and small signal attenuation during the transmission; the power supply system unit is composed of monocrystalline silicon solar panel and high performance rechargeable lithium ion battery. The selection basis of each unit is clarified in detail, and optimization is performed by hardware circuit and software program to further reduce power consumption. The power consumption of the node is calculated by the experiment, and the charging conditions of the solar panel used in the node is tested. The results show that the system can achieve the setting target through the selection and design.展开更多
This paper deals with an innovative low-loss AC switch, named as TBBS （transistor based bidirectional switch）, based on the association of super-gain BJTs developed by the GREMAN laboratory. The main characterizatio...This paper deals with an innovative low-loss AC switch, named as TBBS （transistor based bidirectional switch）, based on the association of super-gain BJTs developed by the GREMAN laboratory. The main characterization results of the super-gain BJT are reminded to identify the key parameters that are essential to build the TBBS. A complete characterization database in static mode of this new AC switch is discussed. In particular, its forward and reverse-biased features have been measured to see the evolution of the DC current gain as a function of the current density. The TBBS makes sense when using the super-gain BJT （bipolar junction transistor） in reverse mode. It means that the reverse DC current gain has to be sufficient （at least higher than l compared with the conventional BJT one）. This new AC switch is bidirectional in current and voltage, totally controllable （turn-on and turn-off） and the most attractive solution in terms of on-state power losses. Further, its manufacturing process is as easier as existing device such as triac.展开更多
The rapid development of artificial intelligence and the Internet of Things has generated an urgent demand for brain-inspired computing systems characterized by high parallel processing capabilities.However,the power ...The rapid development of artificial intelligence and the Internet of Things has generated an urgent demand for brain-inspired computing systems characterized by high parallel processing capabilities.However,the power consumption of most reported artificial synaptic devices remains substantially higher than that of their biological counterparts,which operate at the femtojoule(fJ)level per synaptic event.To this end,this research aims to develop ultralow-power silicon carbide(SiC)plasmonic nanowire network(NWN)-based artificial synaptic devices for using in musical classification neural network system.By leveraging the neural network-like physical architecture of the NWN and the alteration of conductance states at NW-NW junctions,the SiC/SiO_(2)@Ag NWN devices successfully emulate both ultraviolet(UV)visual and electrical synaptic functions under both externally biased electric field modulation mode and zero-bias photoexcitation mode conditions.Furthermore,due to the confinement effects of one-dimensional nanomaterials and the localized surface plasmon resonance(LSPR)induced by Ag nanoparticles,these devices exhibit substantial synaptic responses at ultra-low currents with minimal power consumption.With its low power consumption,the SiC/SiO_(2)@Ag NWN synapses exhibit superior performance in simulating music classification recognition,achieving an accuracy exceeding 95%within 20 epochs.Notably,the innovative SiC NWN structure ensures robust synaptic performance and high precision in neural network computations.This advancement has the potential to drive the development of novel computing architectures,such as spiking neural networks(SNNs),which more closely mimic the operational principles of biological neural networks,thereby facilitating enhanced music information processing.展开更多
Unmanned Aerial Vehicles(UAVs)integrated with Wireless Sensor Networks(WSNs)present a transformative approach to environmental monitoring by enabling real-time,low power,wide-area,and high-resolution data collection.T...Unmanned Aerial Vehicles(UAVs)integrated with Wireless Sensor Networks(WSNs)present a transformative approach to environmental monitoring by enabling real-time,low power,wide-area,and high-resolution data collection.This paper proposes a UAV-based WSN framework designed for efficient ecological data acquisition,including parameters such as temperature,humidity,various gases,detection of motion of a material,and safety features.The system leverages UAVs for dynamic deployment and data retrieval from distributed sensor nodes in remote or inaccessible areas,reducing the reliance on fixed infrastructure.Long Range Communication(LoRa)technology is also integrated with a WSN to enhance network coverage and adaptability issues.The proposed system covers vast areas through LoRa communication ensuring minimal energy consumption and cost-effective sensing capabilities.Field tests and simulation findings show how well the system captures spatiotemporal environmental fluctuations,making it an invaluable tool for monitoring climate change,ecological research,and disaster response.展开更多
This paper designs a high-frequency stable wireless amplitude modulation(AM)system based on a Pierce circuit.The system utilizes an oscillator and comparator to generate a 20 kHz square wave with an adjustable duty cy...This paper designs a high-frequency stable wireless amplitude modulation(AM)system based on a Pierce circuit.The system utilizes an oscillator and comparator to generate a 20 kHz square wave with an adjustable duty cycle,combined with a 41 MHz carrier wave produced by a passive crystal oscillator Pierce circuit.A 100% modulation index amplitude modulation is achieved through the AD835 multiplier.The modulated signal is amplified by a power amplifier circuit and transmitted wirelessly via the transmitter antenna.Upon reception,the signal undergoes two-stage highfrequency amplification before passing through a Schottky diode envelope detector.The NE5532 shaping circuit then restores the square wave.Experimental results demonstrate reliable 11-meter transmission with carrier frequency deviation<0.75% and demodulation error<1%.展开更多
The rapid development of low earth orbit(LEO)satellite communication networks imposes stringent bandwidth,cost,and power consumption requirements.Conventional intradyne detection(ID)architectures struggle with high Do...The rapid development of low earth orbit(LEO)satellite communication networks imposes stringent bandwidth,cost,and power consumption requirements.Conventional intradyne detection(ID)architectures struggle with high Doppler frequency shifts(DFSs),necessitating excessive sampling rates and complex digital signal processing(DSP),resulting in elevated power consumption.This study proposes an inter-satellite polarization division multiplexing self-homodyne detection(PDM-SHD)architecture that compensates for DFSs in the optical domain by co-transmitting a polarization-orthogonal carrier light.The proposed architecture could achieve Nyquist sampling and half-quantization noise,leading to a 53.9%reduction in analog-to-digital converter power consumption under 40 Gbps 16-QAM transmission with a 16 dB signal-to-noise ratio.By demodulating I∕Q axis signals independently with real-valued single-input single-output(SISO)processing,it requires only about 15%DSP complexity and achieves intensity-modulation and direct-detection comparable.SISO processing also has the potential to transmit I and Q components from separate devices or satellites,enabling a flexible satellite communication network.The results demonstrate that the proposed architecture achieves detection sensitivities of−40.8 dBm for 80 Gbps quadrature phase-shift keying transmission and−33.0 dBm for 160 Gbps 16-QAM transmission with Nyquist sampling,whereas the ID architecture can hardly work.The proposed architecture effectively balances satellite power constraints with DSP computational demands for high-speed mega-constellation communications.展开更多
Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 i...Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 is designed in order to acquire gas pressure during cluster bombs dispersion.To meet the requirement of low power consumption,the working states of system＇s modules during data acquisition are elaborated and the equation to calculate the gas pressure change during cylindrical center tube opening the hatch is deduced.The field test is conducted and good test results are obtained.展开更多
基金Project supported by the National High Technology Research and Development Program of China(Grant No.2015AA016902)the National Nature Science Foundation of China(Grant Nos.61435013,61405188,and 61627820)
文摘The power consumption of a variable optical attenuator（VOA） array based on a silica planar lightwave circuit was investigated. The thermal field profile of the device was optimized using the finite-element analysis. The simulation results showed that the power consumption reduces as the depth of the heat-insulating grooves is deeper, the up-cladding is thinner,the down-cladding is thicker, and the width of the cladding ridge is narrower. The materials component and thickness of the electrodes were also optimized to guarantee the driving voltage under 5 V. The power consumption was successfully reduced to as low as 155 mW at an attenuation of 30 dB in the experiment.
基金Supported by the National Basic Research Program of China under Grant No 2013CB632801the National Key Research and Development Program under Grant No 2016YFB0402303+2 种基金the National Natural Science Foundation of China under Grant Nos61435014,61627822,61574136 and 61306058the Key Projects of Chinese Academy of Sciences under Grant No ZDRW-XH-2016-4the Beijing Natural Science Foundation under Grant No 4162060
文摘We report on the design and fabrication of λ-7.2μm distributed feedback quantum cascade lasers lot very high temperature cw operation and low electrical power consumption. The cw operation is reported above 90℃. For a 2-mm-long and 10-μm-wide laser coated with high-reflectivity on the rear facet, more than 170mW of output power is obtained at 20℃ with a threshold power consumption of 2.4 W, corresponding to 30mW with a threshold power consumption of 3.9 W at 90℃. Robust single-mode emission with a side-mode suppression ratio above 25 dB is continuously tunable by the heat sink temperature or injection current.
基金supported in part by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2011-0004114)in part by the Ministry of Knowledge Economy (MKE) and Korea Institute for Advancement in Technology (KIAT) through the Workforce Development Program in Strategic Technology in part by the MKE (The Ministry of Knowledge Economy), Korea, under the CITRC (Convergence Information Technology Research Center) support program (NIPA-2012-C6150-1201-0001) supervised by the NIPA (National IT Industry Promotion Agency)
文摘A new method of prefetching data blocks from the NVCache to the page cache in main memory and cascading prefetching n-blocks from a hard disk to the NVCache together was proposed to reduce the spin-up frequency of a hybrid hard disk drive and thus enhance I/O performance.The proposed method consists of three steps:1) Analyzing the pattern of read requests in block units;2) Determining the number of blocks prefetched to the NVCache;3) Replacing blocks in the NVCache according to the block replacement policy.The proposed method can reduce the latency time of a hybrid hard disk and optimize the power consumption of an IPTV set-top box.Experimental results show that the proposed method provides better average response time compared to an existing adaptive multistream prefetching(AMP) method by 25.17%.It also reduces by 20.83% the average power consumption over that of the existing external caching in energy saving storage system(EXCES) method.
文摘A model of enhancement mode GaAs MESFET (EFET) for low power consumption and low noise applications has been obtained by using a small signal equivalent circuit whose component values are derived from the physical parameters and the bias condition. The dependence of the RF performance and DC power consumption on physical, material and technological parameters of EFET is also studied. The optimum range of the physical parameters is given which is useful for the design of active device of ultra low power consumption MMIC.
基金supported by the Technology Innovation Program(20018954)funded by the Ministry of Trade,Industry&Energy(MOTIE,Korea)by Nano·Material Technology Development Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future Planning(NRF-2016M3A7B4910631)the Engineering Research Center of Excellence(ERC)Program supported by National Research Foundation(NRF),Korean Ministry of Science&ICT(MSIT)(Grant No.NRF-2017R1A5A1014708).
文摘Health monitoring with wearable pulse oximetry(PO)paves the way for personalized,point-of-care health management.Organic PO(OPO)sensors are particularly promising for wearable POs due to their excellent compatibility with flexible,lightweight form factors and design freedom,enabling low power consumption comparable to or even surpassing that of conventional inorganic systems.However,further power reductions are crucial for wearable systems with limited onboard power,and achieving sufficient signal strength at minimal luminance is essential for extended operation.Here,we propose an OPO structure with both ultralow power consumption and low luminance operation.By combining a ring-shaped,vertically stacked two-color organic light-emitting diode(OLED)with a circular organic photodiode(OPD)filling the interior and exterior of the OLED ring,we demonstrate OPO sensors requiring only a fewμW to drive the OLEDs and operable at a few tens of cd/m^(2),demonstrating potentials for continuous health monitoring with extended long-term operation.
文摘A highly sensitive in-situ turbidity sensor with the low power consumption was proposed and evaluated in this study. To meet the practical requirements of the in-situ detection, we have designed the light scattering path, watertight mechanical structure, and ultra-weak scattering light detecting method. Experiments showed that the sensor had a sensitivity of 0.0076 FTU with the concentration range of 0 - 25 FTU and the R-square of 0.9999. The sensor could withstand the water pressure in depth of 1000m and had the low power consumption in the active mode 10.4mA, sleep mode 65 pA with a supply voltage of 8.4V. Southern China Sea buoy experiments indicated that the sensor could work well in the actual in-situ environment. In comparison with sensors of other companies, our sensor had relatively more comprehensive performance.
基金Supported by the Guangdong Special Support Talent Team Program(No.2019BT02H594)the National Natural Science Foundation of China(Nos.42174081,41804071,U2244221)the Guangdong Basic and Applied Basic Research Foundation(No.2021A1515011526)。
文摘The seafloor vector magnetometer is an effective tool for marine geomagnetic surveys and seafloor magnetotelluric(MT)detection.However,the noise,power consumption,cost,and volume characteristics of existing seafloor vector magnetometers are insufficient for practical use.Therefore,a low-noise,low-power-consumption seafloor vector magnetometer that can be used for data acquisition of deep-ocean geomagnetic vector components is developed and presented.A seafloor vector magnetometer mainly consists of a fluxgate sensor,data acquisition module,acoustic release module,glass sphere,frame,burn-wire release,and anchor.A new low-noise data acquisition module and a fluxgate sensor greatly reduce power consumption.Furthermore,compact size is achieved by integrating an acoustic telemetry module and replacing the acoustic release with an external burn-wire release.The new design and magnetometer characteristics reduce the volume of the instrument and the cost of hardware considerably,thereby improving the integrity and deployment efficiency of the equipment.Theoretically,it can operate for 90 days underwater at a maximum depth of 6000 m.The seafloor vector magnetometer was tested in the South China Sea and the Philippine Sea and obtained high-quality geomagnetic data.The deep-water environment facilitates magnetic field data measurements,and the magnetometer has an approximate noise level of 10 pT/rt(Hz)@1 Hz,a peak-to-peak value error of 0.2 nT,and approximate power consumption of 200 mW.The fluxgate sensor can measure the magnetic field in the lower frequency band and realize geomagnetic field measurements over prolonged periods.
基金support by the National Key R&D Program of China(No.2021YFA0717900)the National Natural Science Foundation of China(Nos.12204248,22275098,61905121,51933005)the Jiangsu Funding Program for Excellent Postdoctoral Talent(No.2022ZB399).
文摘Retinal-inspired synaptic phototransistors,which integrate light signal detection,preprocessing,and memory functions,show promising applications in artificial vision sensors.In recent years,it has been reported to construct heterojunction in phototransistors to realize positive photoconductance(PPC)and negative photoconductance(NPC)modulations,thereby achieving visible and infrared wavelength discrimination and various visual functions.However,relatively little attention has been paid to wavelength-dependent switching and reconfigurability between two states(PPC and NPC),limiting further applications for complex simulations of biological visual functions.Here,a mixed organic–inorganic heterojunction synaptic phototransistor was constructed by integrating CsPbBr_(3)nanoplates(NPLs)with strong blue-light absorption and poly(3-hexylthiophene-2,5-diyl)(P3HT)with strong red-light absorption.Compared with the three-dimensional(3D)structure CsPbBr_(3)nanocubes(NCs),the two-dimensional(2D)CsPbBr_(3)NPLs exhibited more efficient charge transfer with P3HT.Based on the individual optical absorption properties in organic–inorganic heterojunction,the device exhibited wavelength-selective and reconfigurable behavior between PPC and NPC.A low power consumption of 0.053 fJ per synaptic event was achieved,which is comparable to a biological synapse.Finally,Drosophila's evasive behavior to food under red and blue light can be successfully demonstrated.This work demonstrates the future potential of synaptic phototransistors for visuomorphic computing.
文摘A test pattern generator （TPG） which can highly reduce the peak power consumption during built-in self-test （BIST） application is proposed. The proposed TPG, called LPpe-TPG, consists of a linear feedback shift register （LFSR） and some control circuits. A procedure is presented firstly to make compare vectors between pseudorandom test patterns by adding some circuits to the original LFSR and secondly to insert some vectors between two successive pseudorandom test patterns according to the ordinal selection of every two bits of the compare vector. Then the changes between any successive test patterns of the test set generated by the LPpe-TPG are not more than twice. This leads to a decrease of the weighted switching activity （WSA） of the circuit under test （CUT） and therefore a reduction of the power consumption. Experimental results based on some ISCAS＇ 85 benchmark circuits show that the peak power consumption has been reduced by 25.25% to 64.46%. Also, the effectiveness of our approach to reduce the total and average power consumption is kept, without losing stuck-at fault coverage.
基金Project supported by the Hi-Tech Research and Development Program (863) of China (No. 2006AA01Z226)the Scientific Research Foundation of Huazhong University of Science and Technol-ogy (No. 2006Z001B), China
文摘Using composite field arithmetic in Galois field can result in the compact Rijndael S-Box. However, the power con- sumption of this solution is too large to be used in resource-limited embedded systems. A full-custom hardware implementation of composite field S-Box is proposed for these targeted domains in this paper. The minimization of power consumption is implemented by optimizing the architecture of the composite field S-Box and using the pass transmission gate (PTG) to realize the logic functions of S-Box. Power simulations were performed using the netlist extracted from the layout. HSPICE simulation results indicated that the proposed S-Box achieves low power consumption of about 130 μW at 10 MHz using 0.25 μm/2.5 V technology, while the consumptions of the positive polarity reed-muller (PPRM) based S-Box and composite field S-Box based on the conventional CMOS logic style are about 240 μW and 420 μW, respectively. The simulations also showed that the presented S-Box obtains better low-voltage operating property, which is clearly relevant for applications like sensor nodes, smart cards and radio frequency identification (RFID) tags.
文摘A study of wireless technologies for IoT applications in terms of power consumption has been presented in this paper. The study focuses on the importance of using low power wireless techniques and modules in IoT applications by introducing a comparative between different low power wireless communication techniques such as ZigBee, Low Power Wi-Fi, 6LowPAN, LPWA and their modules to conserve power and longing the life for the IoT network sensors. The approach of the study is in term of protocol used and the particular module that achieve that protocol. The candidate protocols are classified according to the range of connectivity between sensor nodes. For short ranges connectivity the candidate protocols are ZigBee, 6LoWPAN and low power Wi-Fi. For long connectivity the candidate is LoRaWAN protocol. The results of the study demonstrate that the choice of module for each protocol plays a vital role in battery life due to the difference of power consumption for each module/protocol. So, the evaluation of protocols with each other depends on the module used.
基金supported by the National Natural Science Foundation of China(NSFC)(No.52372131).
文摘The surge in data volume and algorithmic complexity necessitates the development of highly integrated,low-power,and high-performance electronic components.Conventional complementary metal-oxide-semiconductor(CMOS)inverters,which rely solely on isotropic two-dimensional materials,encounter limitations due to their single voltage output,thereby impeding the miniaturization of integrated circuits.In this study,we introduce anisotropic CMOS inverters based on n-ReS_(2)and p-WSe_(2),which demonstrate distinct voltage transfer characteristics across various crystalline orientations.These inverters exhibit the lowest voltage gain along the a-axis of ReS_(2)flakes,whereas they possess the highest voltage gain and the lowest static power consumption along the b-axis.By optimizing the gate dielectric on substrates,the inverter achieves an enhanced voltage gain of 30.8 and an ultra-low power consumption of 5.4 pW along the b-axis direction,when fabricated on a 35 nm Al_(2)O_(3)substrate deposited via atomic layer deposition(ALD)method.Additionally,it captures a clear dynamic switching behavior at a supply voltage of 3 V under a 20 Hz square wave input signal.This study proposes a potential approach to circuit miniaturization by leveraging anisotropic two-dimensional materials for the integration of diverse voltage transfer characteristics within a single logic device,thereby achieving a combination of low power consumption and high-density integration.
基金supported by the National Natural Science Foundation of China(No.61471233)Shanghai Sailing Program(No.21YF1431400)。
文摘There is a great demand for high-performance hydrogen sulfide(H_(2)S)sensors with low operating temperatures.Ag/In_(2)O_(3)hexagonal tubes with different proportions were prepared by the calcination of Ag+-impregnated indium-organic frameworks(CPP-3(In)),and the developed sensors exhibit enhanced gas-sensing performance toward H_(2)S.Gas sensing measurements indicate that the response of Ag/In_(2)O_(3)(2.5 wt%)sensor to 5 ppm H_(2)S has the highest response(119),operated at 70℃.The Ag/In_(2)O_(3)(2.5 wt%)based sensor exhibits short response time(20 s),low detection limit(300 ppb),and good selectivity toward H_(2)S gas,which imply that the CPP-3(In)-derived Ag/In_(2)O_(3)hexagonal tube is a promising candidate to be constructed a low power-consumption H_(2)S sensor.
基金Supported by the Special Foundation Program of President(14007)the Science and Technology Support Program of Tianjin(14ZCZDNC00005)+3 种基金the Modern Agricultural Industry System for Vegetables of Tianjin(ITTVRS2017018)the Commercialization and Promotion of Agricultural Research Findings of Tianjin(201601220)China Spark Program(2015GA610013)the Special Foundation of President(16005)~~
文摘In this study, the green energy saving of greenhouse sensor node is de- signed to reduce the system power consumption and high efficiency. The green renewable solar energy resources are used as the energy source of nodes; the lowenergy consumed and cost effective MSP430 chip is used as the main control chip of the processor unit; the transmission frequency of the wireless transmission unit is 433 MHz, which has the characteristics of low power consumption, high signal strength, long transmission distance and small signal attenuation during the transmission; the power supply system unit is composed of monocrystalline silicon solar panel and high performance rechargeable lithium ion battery. The selection basis of each unit is clarified in detail, and optimization is performed by hardware circuit and software program to further reduce power consumption. The power consumption of the node is calculated by the experiment, and the charging conditions of the solar panel used in the node is tested. The results show that the system can achieve the setting target through the selection and design.
文摘This paper deals with an innovative low-loss AC switch, named as TBBS （transistor based bidirectional switch）, based on the association of super-gain BJTs developed by the GREMAN laboratory. The main characterization results of the super-gain BJT are reminded to identify the key parameters that are essential to build the TBBS. A complete characterization database in static mode of this new AC switch is discussed. In particular, its forward and reverse-biased features have been measured to see the evolution of the DC current gain as a function of the current density. The TBBS makes sense when using the super-gain BJT （bipolar junction transistor） in reverse mode. It means that the reverse DC current gain has to be sufficient （at least higher than l compared with the conventional BJT one）. This new AC switch is bidirectional in current and voltage, totally controllable （turn-on and turn-off） and the most attractive solution in terms of on-state power losses. Further, its manufacturing process is as easier as existing device such as triac.
基金supported by the National Natural Science Foundation of China (11875032)Natural Science Foundation of Shaanxi Province (2023-JC-QN-0268)+3 种基金Shaanxi Fundamental Science Research Project for Mathematics and Physics (23JSQ004)Shaanxi Provincial Department of Education (23JK0341)Foundations of Shaanxi Province (2023-JC-YB-022)Shaanxi Fundamental Science Research Project for Mathematics and Physics (22JSQ006)。
文摘The rapid development of artificial intelligence and the Internet of Things has generated an urgent demand for brain-inspired computing systems characterized by high parallel processing capabilities.However,the power consumption of most reported artificial synaptic devices remains substantially higher than that of their biological counterparts,which operate at the femtojoule(fJ)level per synaptic event.To this end,this research aims to develop ultralow-power silicon carbide(SiC)plasmonic nanowire network(NWN)-based artificial synaptic devices for using in musical classification neural network system.By leveraging the neural network-like physical architecture of the NWN and the alteration of conductance states at NW-NW junctions,the SiC/SiO_(2)@Ag NWN devices successfully emulate both ultraviolet(UV)visual and electrical synaptic functions under both externally biased electric field modulation mode and zero-bias photoexcitation mode conditions.Furthermore,due to the confinement effects of one-dimensional nanomaterials and the localized surface plasmon resonance(LSPR)induced by Ag nanoparticles,these devices exhibit substantial synaptic responses at ultra-low currents with minimal power consumption.With its low power consumption,the SiC/SiO_(2)@Ag NWN synapses exhibit superior performance in simulating music classification recognition,achieving an accuracy exceeding 95%within 20 epochs.Notably,the innovative SiC NWN structure ensures robust synaptic performance and high precision in neural network computations.This advancement has the potential to drive the development of novel computing architectures,such as spiking neural networks(SNNs),which more closely mimic the operational principles of biological neural networks,thereby facilitating enhanced music information processing.
文摘Unmanned Aerial Vehicles(UAVs)integrated with Wireless Sensor Networks(WSNs)present a transformative approach to environmental monitoring by enabling real-time,low power,wide-area,and high-resolution data collection.This paper proposes a UAV-based WSN framework designed for efficient ecological data acquisition,including parameters such as temperature,humidity,various gases,detection of motion of a material,and safety features.The system leverages UAVs for dynamic deployment and data retrieval from distributed sensor nodes in remote or inaccessible areas,reducing the reliance on fixed infrastructure.Long Range Communication(LoRa)technology is also integrated with a WSN to enhance network coverage and adaptability issues.The proposed system covers vast areas through LoRa communication ensuring minimal energy consumption and cost-effective sensing capabilities.Field tests and simulation findings show how well the system captures spatiotemporal environmental fluctuations,making it an invaluable tool for monitoring climate change,ecological research,and disaster response.
文摘This paper designs a high-frequency stable wireless amplitude modulation(AM)system based on a Pierce circuit.The system utilizes an oscillator and comparator to generate a 20 kHz square wave with an adjustable duty cycle,combined with a 41 MHz carrier wave produced by a passive crystal oscillator Pierce circuit.A 100% modulation index amplitude modulation is achieved through the AD835 multiplier.The modulated signal is amplified by a power amplifier circuit and transmitted wirelessly via the transmitter antenna.Upon reception,the signal undergoes two-stage highfrequency amplification before passing through a Schottky diode envelope detector.The NE5532 shaping circuit then restores the square wave.Experimental results demonstrate reliable 11-meter transmission with carrier frequency deviation<0.75% and demodulation error<1%.
基金supported by the National Natural Science Foundation of China(Grant Nos.62401220,62205111,and 62225110)the Major Program(JD)of Hubei Province(Grant No.2023BAA001-1)the Key Research and Development Program of Hubei Province of China(Grant No.2025BAB007).
文摘The rapid development of low earth orbit(LEO)satellite communication networks imposes stringent bandwidth,cost,and power consumption requirements.Conventional intradyne detection(ID)architectures struggle with high Doppler frequency shifts(DFSs),necessitating excessive sampling rates and complex digital signal processing(DSP),resulting in elevated power consumption.This study proposes an inter-satellite polarization division multiplexing self-homodyne detection(PDM-SHD)architecture that compensates for DFSs in the optical domain by co-transmitting a polarization-orthogonal carrier light.The proposed architecture could achieve Nyquist sampling and half-quantization noise,leading to a 53.9%reduction in analog-to-digital converter power consumption under 40 Gbps 16-QAM transmission with a 16 dB signal-to-noise ratio.By demodulating I∕Q axis signals independently with real-valued single-input single-output(SISO)processing,it requires only about 15%DSP complexity and achieves intensity-modulation and direct-detection comparable.SISO processing also has the potential to transmit I and Q components from separate devices or satellites,enabling a flexible satellite communication network.The results demonstrate that the proposed architecture achieves detection sensitivities of−40.8 dBm for 80 Gbps quadrature phase-shift keying transmission and−33.0 dBm for 160 Gbps 16-QAM transmission with Nyquist sampling,whereas the ID architecture can hardly work.The proposed architecture effectively balances satellite power constraints with DSP computational demands for high-speed mega-constellation communications.
文摘Aiming at harsh environment of cluster bombs center tube explosion dispersion and difficulties in installation of traditional test systems,a storage test system based on 16-bit ultra-low power microcontroller MSP430 is designed in order to acquire gas pressure during cluster bombs dispersion.To meet the requirement of low power consumption,the working states of system＇s modules during data acquisition are elaborated and the equation to calculate the gas pressure change during cylindrical center tube opening the hatch is deduced.The field test is conducted and good test results are obtained.
