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51.
Three types of GaAs monolithic microwave integrated circuits (MMICs) were RF high temperature accelerated life tested to determine the median time before failure (MTBF). Life testing was performed under the d.c. bias conditions and RF input power levels the MMICs would be expected to use under actual operating conditions. the accelleration condition was to raise the base-plate temperature high enough to result in degradation in approximately 1000 hours at the highest test temperature. Because the MMICs were designed for power applications, the input signal level was large enough to cause approximately 1 dB compression. Device failure was defined as a 20 per cent decrease in output power as measured at 125°C, or room temperature when the temperature control system was turned off. Under these conditions the MTBF extrapolated to a channel temperature of 125°C varied between 8 × 103 hours and 2 × 105 hours depending on the MMIC type. The primary failure mode appeared to be surface leakage currents under the passivation layer.  相似文献   
52.
Wide frequency bandwidth has been internationally allocated for unlicensed operation around the oxygen absorption frequency at 60 GHz. A power amplifier and a low noise amplifier are presented as building blocks for a T/R-unit at this frequency. The fabrication technology was a commercially available 0.15 m gallium arsenide (GaAs) process featuring pseudomorphic high electron mobility transistors (PHEMT). Using on-wafer tests, we measured a gain of 13.4 dB and a +17 dBm output compression point for the power amplifier at 60 GHz centre frequency when the MMIC was biased to 3 volts Vdd. At the same frequency, the low noise amplifier exhibited 24 dB of gain with a 3.5 dB noise figure. The AM/AM and AM/PM characteristics of the power amplifier chip were obtained from the large-signal S-parameter measurement data. Furthermore, the power amplifier was assembled in a split block package, which had a WR-15 waveguide interface in input and output. The measured results show a 12.5 dB small-signal gain and better than 8 dB return losses in input and output for the packaged power amplifier.Mikko Kärkkäinen received the M.Sc. degree in electrical engineering from the Helsinki University of Technology, Espoo, Finland, in 2000, and is currently working toward the Ph.D. degree at the Electronic Circuit Design Laboratory, Helsinki University of Technology. He is interested in millimetre wave circuit design.Mikko Varonen received the M.Sc. degree in electrical engineering from the Helsinki University of Technology, Espoo, Finland, in 2002. He is currently working toward the Ph.D. degree in electrical engineering at the Electronic Circuit Design Laboratory, Helsinki University of Technology. His research interests involve millimetre-wave integrated circuits.Pekka Kangaslahti received the M.Sc. and Ph.D. degrees in electrical engineering from the Helsinki University of Technology, Finland, in 1992 and 1999, respectively. Since 1999 he has been a visiting scientist at the NASA Jet Propulsion Laboratory, Pasadena, USA. His research interests include nonlinear microwave and millimetre wave monolithic circuits, especially for signal generation in telecommunication and radar applications.Kari A. I. Halonen was born in Helsinki, Finland, on May 23, 1958. He received the M.Sc. degree in electrical engineering from Helsinki University of Technology, Finland, in 1982, and the Ph.D. degree in electrical engineering from the Katholieke Universiteit Leuven, in Heverlee, Belgium, in 1987.From 1982 to 1984 he was employed as assistant at Helsinki University of Technology and as research assistant at the Technical Research Center of Finland. From 1984 to 1987 he was a research assistant at the E.S.A.T. Laboratory of the Katholieke Universiteit Leuven, enjoying also a temporary grant of the Academy of Finland. Since 1988 he has been with the Electronic Circuit Design Laboratory, Helsinki University of Technology, as senior assistant (1988–1990), and the director of the Integrated Circuit Design Unit of the Microelectronics Center (1990–1993). He was on leave of absence the academic year 1992–93, acting as R&D manager in Fincitec Inc., Finland. From 1993 to 1996 he has been an associate professor, and since 1997 a full professor at the Faculty of Electrical Engineering and Telecommunications, Helsinki University of Technology. He became the Head of Electronic Circuit Design Laboratory year 1998. From 1997 to 1999 he was an associate editor of IEEE Transactions on Circuits and Systems I. He has been a guest editor for IEEE Journal of Solid-State Circuits and the Technical Program Committee Chairman for European Solid-State Circuits Conference year 2000. He has been awarded the Beatrice Winner Award in ISSCC02 Conference year 2002.  相似文献   
53.
雷达用微波功率器件的发展趋势   总被引:2,自引:2,他引:0  
本文从雷达技术发展的角度阐述了雷达用微波功率器件的发展趋势,并指出今后将主要发展MPM,MMIC,毫米波真空器件和真空微电子器件。  相似文献   
54.
报道了一种低相位噪声VCOMMIC芯片,采用传统的源端反馈形成负阻来消除谐振回路中的寄生电阻,通过合理的输出匹配实现起振条件并抑制谐波,利用南京电子器件研究所0.15μmGaAsMHEMT工艺,研制的Ka波段GaAsMHEMT压控振荡器,典型振荡频率为39.34GHz,频率变化范围38.6~41.3GHz之间,调谐带宽2.7GHz,典型输出功率6.97dBm,频偏100kHz,相位噪声为-81.1dBc/Hz。  相似文献   
55.
A new wafer-level 3D packaging structure with Benzocyclobutene (BCB) as interlayer dielectrics (ELDs) for multichip module fabrication is proposed for application in the Ku-band wave. The packaging structure consists of two layers of BCB films and three layers of metallized films, in which the monolithic microwave IC (MMIC), thin film resistors, striplines and microstrip lines are integrated. Wet etched cavities fabricated on the silicon substrate are used for mounting active and passive components. BCB layers cover the components and serve as ILDs for interconnections. Gold bumps are used as electric interconnections between different layers, which eliminates the need to prepare vias by costly dry etching and deposition processes. In order to get high-quality BCB films for the subsequent chemical mechanical planarization (CMP) and multilayer metallization processes, the BCB curing profile is optimized and the roughness of the BCB film after the CMP process is kept lower than 10 nm. The thermal, mechanical and electrical properties of the packaging structure are investigated. The thermal resistance can be controlled below 2 ℃/W. The average shear strength of the gold bumps on the BCB surface is around 70 N/mm~2. The performances of MMIC and interconnection structure at high frequencies are optimized and tested. The 5 -parameters curves of the packaged MMIC shift slightly showing perfect transmission character. The insertion loss change after the packaging process is less than 1 dB range at the operating frequency and the return loss is less than -8 dB from 10 to 15 GHz.  相似文献   
56.
A novel symmetrical microwave power sensor based on MEMS technology is presented. In this power sensor, the left section inputs the microwave power, while the right section inputs the DC power. Because of its symmetrical structure, this power sensor provides more accurate microwave power measurement capability without mismatch uncertainty and temperature drift. The loss caused by the microwave signal is simulated in this power sensor. This power sensor is designed and fabricated using GaAs MMIC technology. And it is measured in the frequency range up to 20 GHz with an input power in the 0-80 mW range. Over the 80 mW dynamic range, the sensitivity can achieve about 0.2 mV/mW. The difference between the input power in the two sections is below 0.1% for an equal output voltage. In short, the key aspect of this power sensor is that the microwave power measurement is replaced with a DC power measurement.  相似文献   
57.
A highly efficient and compactly integrated balanced power amplifier (PA) for W‐CDMA handset applications is presented. To overcome the size limit of a typical balanced PA, a bulky input divider is integrated into a PA MMIC, and a complex output network is replaced with simple lumped‐element networks. For efficiency improvement at the low output power level, one of the two amplifiers in parallel is deactivated and the other is partially operated with corresponding load impedance optimization. The implemented PA shows excellent average current consumption of 34.5 mA in urban and 56.3 mA in suburban environments, while exhibiting very good load‐insensitivity under condition of VSWR=4:1.  相似文献   
58.
介绍了24~38GHz低噪声放大器MMIC的研制。分析了微波晶体管放大器的噪声特性,针对噪声系数和增益,利用软件进行电路仿真优化和电磁场分析,设计制作电路版图,在标准3 in GaAs工艺线进行工艺制作。采用电子束制作0.20μm“T”形栅,利用选择腐蚀的方法准确控制有源器件的Idss和Vp,微波测试结果为在频带内的噪声系数小于3.8dB,小信号增益大于13dB,增益平坦度小于±0.6dB,输入和输出驻波比小于2:1.微波性能与NORTHROP GRUMMAN公司的同类产品ALH140C的水平相当。  相似文献   
59.
This paper presents a new millimeter-wave (MMW) ultra wideband (UWB) transmitter MMIC which has been developed in an OMMIC 0.1 μm GaAs PHEMT foundry process (ft = 100 GHz) for 22-29 GHz vehicular radar systems. The transmitter is composed of an MMW negative resistance oscillator (NRO), a power amplifier (PA), and two UWB pulse generators (PGs). In order to convert the UWB pulse signal to MMW frequency and reduce the total power consumption, the MMW NRO is driven by one of the UWB pulse generators and the power amplifier is triggered by another UWB pulse generator. The main advantages of this transmitter are: new design, simple architecture, high-precision distance measurements, infinite ON/OFF switch ratio, and low power consumption. The total power consumption of the transmitter MMIC is 218 mW with a peak output power of 5.5 dBm at 27 GHz.  相似文献   
60.
许晓丽  张斌  邵凯 《半导体学报》2004,25(3):321-324
介绍了一种预失真线性化单片电路,该电路单电源工作,采用预失真技术结合有源反馈的方法,完成了单片预失真线性化电路的研制.预失真线性化单片电路采用75 m m Ga As MMIC工艺研制,芯片面积约为4 mm2 .结果表明,2 .1GHz时此预失真单片电路可改善放大器的三阶互调分量9d B  相似文献   
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