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101.
A low-noise amplifier (LNA) operated at 40 GHz is designed. An improved cascode configuration is proposed and the design of matching networks is presented. Short-circuited coplanar waveguides (CPWs) were used as inductors to achieve a high Q-factor. The circuit was fabricated in a 0.13-μm SiGe BiCMOS technology with a transistor transit frequency fT of 103 GHz. The chip area is 0.21 mm2. The LNA has one cascode stage with a-3 dB bandwidth from 34 to 44 GHz. At 40 GHz, the measured gain is 8.6 dB; the input return loss, S11, is-16.2 dB; and the simulated noise figure is 5 dB. The circuit draws a current of only 3 mA from a 2.5 V supply. 相似文献
102.
Emanuele Bottino Paolo Massobrio Sergio Martinoia Giacomo Pruzzo Maurizio Valle 《Microelectronics Journal》2009,40(12):1779-1787
This paper reports the design and the experimental results of a fully integrated, low-noise, low-power standard CMOS preamplifier circuit used to record the extracellular electrophysiological activity of in vitro biological neuronal cultures. Our goal is to use the preamplifier in a fully integrated, multi-channel, bi-directional neuro-electronic interface.Among others, two main requirements must be addressed when designing such kind of integrated recording systems: noise performance and very low frequency disturbance rejection. These two requirements need to be satisfied together with a small silicon area design, to be able to integrate a large number of recording channels (i.e. up to thousands) onto a single die. A prototype preamplifier circuit has been designed and implemented; in this paper we report the experimental results.While satisfying the above requirements, our circuit offers state-of-the-art smallest area occupation (0.13 mm2) and consumes 4.5 μW. Sub-threshold-biased lateral pnp transistors, used to implement very high resistance value integrated resistors, have been characterized to determine the resistance spread.The fabricated prototype, coupled with a commercial Micro-Electrode Array (MEA), has been successfully employed to record the extracellular electrophysiological spontaneous activity, both of muscular cardiac cells (cardiomyocytes) and of spinal cord neurons from murines. 相似文献
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基于使LNA在5.5G~6.5G Hz频段内具有优良性能的目的,本设计中采用了具有低噪声、较高关联增益、PHEMT技术设计的ATF-35176晶体管,电路采用二级级联放大的结构形式,利用微带电路实现输入输出和级间匹配,通过ADS软件提供的功能模块和优化环境对电路增益、噪声系数、驻波比、稳定系数等特性进行了研究设计,最终... 相似文献
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针对Si基双极型低噪声放大器(LNA),用脉冲调制150MHz射频信号在其输入端进行了能量注入实验,研究结果表明Si基LNA的噪声系数和增益特性都足注人能最的敏感参数.样品解削和电路仿真显示能量作用使LNA内部晶体管出现基极/发射极金属化损伤,基极金.半接触电阻增大导致了LNA噪声系数增大,而Si基双极器件hFE随时间正向漂移损伤模式使LNA增益随注入能量的增加而增大.研究表明,由于能量作用下损伤效应的复杂性,以往可靠性研究中单纯采用增益的变化来衡量器件与电路的损伤效应的方法是不全面的. 相似文献
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Marnus Weststrate Anindya Mukherjee Saurabh Sinha Michael Schröter 《International Journal of Electronics》2013,100(1):36-47
Although it is desirable for a transistor model to be as accurate as possible, the extraction of model parameters from fabricated transistors is a time-consuming and often costly process. An investigation of the sensitivity of low-noise amplifier (LNA) performance characteristics to individual parameters of the physics-based standard HBT model HICUM/L2 was, therefore, done to gain a preliminary insight into the most important parameters for transistors used in actual circuits. This can potentially allow less strenuous accuracy requirements on some parameters which would ease the extraction process. Both a narrow- and wideband LNA configuration were investigated. It was found that the series resistance parameters have a large impact on LNA gain, S 11 and noise figure performance in both cases. Since the narrow-band LNA relied heavily on the transistor characteristics to provide a proper matching, it was also very sensitive to changes in the parameters used in modelling the high-frequency current gain and depletion capacitances of the transistor. 相似文献
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Runbo Ma Wenmei Zhang Guorui Han Li Li Xinwei Chen Liping Han 《International Journal of Electronics》2013,100(4):585-595
A simple method for the design of two-dimensional circularly symmetric recursive digital filters is presented. This method makes use of a one-dimensional analogue filter and an additional zero-phase polynomial in the numerator to approximate a desired magnitude response. The number of coefficients required to be optimized is reduced and the stability of the filter can be guaranteed. Generally, moderately precise filters can be obtained using this design method. 相似文献