传感器信号的非线性软件补偿

传感器信号非线性误差软件补偿采用校正函数法,函数拟合法,及线性插值查表法。校正函数法将运算规则存入微处理器,通过校正函数运算进行补偿。函数拟合法采用多项式、解析等拟合函数,通过最小二乘法求出拟合函数实现补偿。线性插值查表法经分段处理,确定测量值区间端点对应值,用查找表进行非线性校正。     

Group-based user pairing for virtual MIMO in LTE

A user pairing method is proposed to improve the throughput gain of virtual multiple input multiple output (virtual MIMO) in 3G long-term evolution (LTE).The approach taken in this study separated the user pairing into four steps 1) the users are divided into two groups according to their signal-to-noise ratio (SNR), and different user pairing metrics are proposed for each group; 2) the scheduler chooses a user for transmitting by a given rule; 3) the scheduler searches the pairing candidate for the selected user in each group; 4) the scheduler chooses the final pairing user from the co-group and crossover-group candidates by using a marginal utility function, to balance fairness and efficiency.The method can improve the throughput of users with high SNR, and guarantee fairness for users with low SNR, so it can be used in 3G LTE systems.The article provides both theoretical analysis and simulation results to support the idea.     

Capillary‐Bridge Mediated Assembly of Conjugated Polymer Arrays toward Organic Photodetectors

Large‐scale patterning of high‐quality organic semiconductors is crucial for the fabrication of optoelectronic devices with high efficiency and low cost. Yet, owing to the uncontrollable dewetting dynamics of organic liquid in conventional solution patterning techniques, large defect density of organic architectures is inevitable, which is detrimental to the device performance. To address this challenge, herein a capillary‐bridge‐mediated assembly technique is developed for regulating the dewetting process, yielding large‐scale 1D microstructure ordered arrays. The 1D arrays organic photodetectors exhibit a high optoelectronic performance of light on/off ratio exceeding 100, responsivity of 3.24 A W^?1, detectivity of 3.20 × 10¹¹ Jones and fast response speed, showing a great improvement compared with spin‐coated membrane devices. In addition, the significant enhancement of the device photodetection under the electronic field modulation is investigated by applying a back‐gate voltage and explained with the photocurrent predominating in the OFF state and the neglected thermocurrent and tunneling current promoting in the ON state of the phototransistor devices. The research offers a new insight for the facile fabrication of large‐scale integrated photodetectors and other organic devices based on patterned conjugated polymers.     

对称电极组空间位阻效应交流电渗流研究

建立了一种对称电极组交流电渗流微泵结构,通过改变相邻电极间的AC信号相位,可以方便地实现对微通道流向的控制。根据双电层离子数的空间位阻效应修正,数值求解了双电层Poisson-Boltzmann方程和液体流动Navier-Stokes方程,得到了对称电极组交流电渗微泵的流动特性。分析了微泵流速与交流电压幅值、频率等参数的关系特性,并与双电层Debye-Hückel线性解进行比较。结果表明,空间位阻效应修正在低电压时与Debye-Hückel线性解一致,但是在高电压时会产生高频反向流。     

长周期莫尔光栅的理论研究

长周期光纤光栅作为一种损耗型的带阻滤波器，在光纤通信和光纤传感器领域有着广泛的应用。结合长周期光纤光栅的传输特性，利用传输矩阵法对多种长周期莫尔光栅的透射谱进行了理论模拟。分析结果表明，莫尔光栅技术在制作高性能的相移长周期光栅和变迹长周期光栅上有着很好的应用前景。     

A 1-V 86-mW-RX 53-mW-TX Single-Chip CMOS Transceiver for WLAN IEEE 802.11a

A 1-V WLAN IEEE 802.11a CMOS transceiver integrates all building blocks on a single chip including a transformer-feedback VCO and a stacked divider for the frequency synthesizer and 8-bit IQ ADCs and 8-bit IQ DACs. Fabricated in a 0.18-mum CMOS process and operated at a single 1-V supply, the receiver and the transmitter consume 85.7 mW and 53.2 mW, including the frequency synthesizer, respectively. The total chip area with pads is 12.5 mm².     

Colossal Barocaloric Effect by Large Latent Heat Produced by First-Order Intersite-Charge-Transfer Transition

Materials which show novel thermal properties can be used to make highly efficient and environmentally friendly energy systems for thermal energy storage and refrigeration through caloric effects. An A-site-ordered quadruple perovskite-structure oxide, NdCu₃Fe₄O₁₂, is found to release significant latent heat, 25.5 kJ kg⁻¹ (157 J cc⁻¹), at the intersite-charge-transfer transition temperature near room temperature. The transition is first-order and accompanied by an unusual magnetic ordering and a large negative-thermal-expansion-like volume change, and thus, it causes a large entropy change (84.2 J K⁻¹ kg⁻¹). The observed entropy change is comparable to the largest changes reported in inorganic solid materials, and more importantly, it is utilized through a colossal barocaloric effect. The adiabatic temperature change by applying 5.1 kbar pressure is estimated to reach 13.7 K, which means efficient refrigeration can be realized through this effect.     

300 ps switching of spontaneous emission by quantum confined fieldeffect in a light emitting triode

A high-speed switching, as fast as 300 ps, of spontaneous emission is achieved in the recently developed quantum-confined field-effect light emitting triode. As a result of the combination of the field control of radiative life time with modulation of carrier-generation rate, the light intensity modulation does not rely on changes in carrier population at all but on the field control of the radiative life time in the quantum well structure of the device. Elaborated is the allowance for the deviation of the modulation depth of injection current from an optimum value in the modulation scheme     

Assessing material qualities and efficiency limits of III–V on silicon solar cells using external radiative efficiency

The paper presents a quantitative approach to the investigation and comparison of the material qualities of III–V on silicon (III–V/Si) solar cells by using external radiative efficiencies. We use this analysis to predict the limiting efficiencies and evaluate the criteria of material quality in order to achieve high‐efficiency III–V/Si solar cells. This result yields several implications for the design of high‐efficiency III–V/Si solar cells. Copyright © 2016 John Wiley & Sons, Ltd.     

Incombustible Polymer Electrolyte Boosting Safety of Solid-State Lithium Batteries: A Review

Lithium-ion batteries with their portability, high energy density, and reusability are frequently used in today's world. Under extreme conditions, lithium-ion batteries leak, burn, and even explode. Therefore, improving the safety of lithium-ion batteries has become a focus of attention. Researchers believe using a solid electrolyte instead of a liquid one can solve the lithium battery safety issue. Due to the low price, good processability and high safety of the solid polymer electrolytes, increasing attention have been paid to them. However, polymer electrolytes can also decompose and burn under extreme conditions. Moreover, lithium dendrites are formed continuously due to the uneven charge distribution on the surface of the lithium metal anode. A short circuit caused by a lithium dendrite can cause the battery to thermal runaway. As a result, the safety of polymer solid-state batteries remains a challenge. In this review, the thermal runaway mechanism of the batteries is summarized, and the batteries abuse test standard is introduced. In addition, the recent works on the high-safety polymer electrolytes and the solution strategies of lithium anode problems in polymer batteries are reviewed. Finally, the development direction of safe polymer solid lithium batteries is prospected.