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A 1.8-2.6 GHz CMOS VCO with switched capacitor array and switched inductor array

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Journal of Semiconductors 2010年第2期31卷 29-32页

作者：王小松黄水龙陈普锋张海英 Institute of Microelectronics.Chinese Academy of Sciences

The design of a 1.76-2.56 GHz CMOS voltage-controlled oscillator（VCO） with switched capacitor array and switched inductor array is *** in 0.18μm 1P6M CMOS technology,the VCO achieves a 37% frequency tuning *** measured phase noise varies between -118.5 dBc/Hz and -122.8 dBc/Hz at 1 MHz offset across the tuning *** consumption is about 14.4 mW with a 1.8 V *** on a reconfigurable LC tank with switched capacitor array and switched inductor array,the tuning range is analyzed and derived in terms of design parameters,yielding useful equations to guide the circuit design.

关键词： tuning range phase noise MOS VCO switched capacitor array switched inductor array

A Monolithic InGaP/GaAs HBT VCO for 5GHz Wireless Applications

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Journal of Semiconductors 2007年第6期28卷 823-828页

作者：陈立强张健李志强陈普锋张海英中国科学院微电子研究所北京100029

A monolithic voltage controlled oscillator （VCO） based on negative resistance principle is presented uti-lizing commercially available InGaP/GaAs hetero-junction bipolar transistor （HBT） technology. This VCO is de-signed for 5GHz-band wireless applications. Except for bypass and decoupled capacitors,no external component is needed for real application. Its measured output frequency range is from 4.17 to 4.56GHz,which is very close to the simulation one. And the phase noise at an offset frequency of 1MHz is -112dBc/Hz. The VCO core dissipates 15.5mW from a 3.3V supply,and the output power ranges from 0 to 2dBm. To compare with other oscillators,the figure of merit is calculated,which is about -173.2dBc/Hz. Meanwhile, the principle and design method of nega-tive resistance oscillator are also discussed.

关键词： VCO MMIC wireless communication InGaP/GaAs HBT

A 6-9 GHz 5-band CMOS synthesizer for MB-OFDM UWB

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Journal of Semiconductors 2010年第7期31卷 72-78页

作者：陈普锋李志强王小松张海英叶甜春 Institute of Microelectronics Chinese Academy of Sciences

An ultra-wideband frequency synthesizer is designed to generate carrier frequencies for 5 bands distributed from 6 to 9 GHz with less than 3 ns switching *** incorporates two phase-locked loops and one single-sideband （SSB） mixer.A 2-to-1 multiplexer with high linearity is proposed.A modified wideband SSB mixer,quadrature VCO, and layout techniques are also *** synthesizer is fabricated in a 0.18μm CMOS process and operates at 1.5-1.8 V while consuming 40 mA *** measured phase noise is -128 dBc/Hz at 10 MHz offset,and the sideband rejection is -22 dBc at 7.656 GHz.

关键词： 6-9-GHz frequency synthesizer PLL MB-OFDM UWB CMOS

Characterization of ZnO nanowire field-effect transistors exposed to ultraviolet radiation

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Chinese Physics B 2009年第11期18卷 5020-5023页

作者：黎明张海英郭常新徐静波付晓君陈普锋 Institute of Microelectronics Chinese Academy of Sciences Department of Physic University of Science and Technology of China

A ZnO nanowire （NW） field-effect transistor （FET） is fabricated and characterized, and its characterization of ultraviolet radiation is also investigated. On the one hand, when the radiation time is 5 min, the radiation intensity increases to 5.1μW/cm^2, while the saturation drain current （Idss） of the nanowire FET decreases sharply from 560 to 320 nA. The field effect mobility（μ） of the ZnO nanowire FET drops from 50.17 to 23.82cm^2/（V·s） at VDS= 2.5V, and the channel resistivity of the FET increases by a factor of 2.0n the other hand, when the radiation intensity is 2.5μW/cm^2, the DC performance of the FET does not change significantly with irradiation time （its performances at irradiation times of 5 and 20 min are almost the same）; in particular, the Idss of NW FET only reduces by about 50 nA. Research is underway to reveal the intrinsic properties of suspended ZnO nanowires and to explore their device

关键词： ZnO nanowire suspended field-effect transistor ultraviolet radiation

A 3GHz Low-Power and Low-Phase-Noise LC VCO with a Self-Biasing Current Source

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Journal of Semiconductors 2008年第11期29卷 2106-2109页

作者：陈普锋李志强黄水龙张海英叶甜春中国科学院微电子研究所北京100029

A fully integrated 3GHz low-power and low-phase-noise voltage-controlled oscillator （VCO） with a self-biasing current source was implemented in a standard 0.18μm CMOS process. A trade-off between noise and power was realized through the optimization of the improved current source. The VCO can be tuned from 2.83 to 3.25GHz with a 13.8% tuning range. The measured phase noise at 1MHz offset is -111dBc/Hz at a frequency of 3.22GHz while the core circuit draws less than 2mA from a 1.8V supply voltage. These results make the circuit suitable for a 5GHz wireless local area network （WLAN） receiver and 3.4 to 3.6GHz world interoperability for microwave access （WiMAX） application.

关键词： 3GHz LC VCO phase noise self-biasing current source CMOS

A wideband frequency synthesizer for a receiver application at multiple frequencies

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Journal of Semiconductors 2010年第3期31卷 80-84页

作者：王小松黄水龙陈普锋雷牡敏李志强张海英 Institute of Microelectronics Chinese Academy of Sciences

An integer-N frequency synthesizer for a receiver application at multiple frequencies was implemented in 0.18μm 1P6M CMOS technology. The synthesizer generates 2.57 GHz, 2.52 GHz, 2.4 GHz and 2.25 GHz local signals for the receiver. A wide-range voltage-controlled oscillator （VCO） based on a reconfigurable LC tank with a binaryweighted switched capacitor array and a switched inductor array is employed to cover the desired frequencies with a sufficient margin. The measured tuning range of the VCO is from 1.76 to 2.59 GHz. From the carriers of 2.57 GHz, 2.52 GHz, 2.4 GHz and 2.25 GHz, the measured phase noises are -122.13 dBc/Hz, -122.19 dBc/Hz, -121.8 dBc/Hz and -121.05 dBc/Hz, at 1 MHz offset, respectively. Their in-band phase noises are -80.09 dBc/Hz, -80.29 dBc/Hz, -83.05 dBc/Hz and -86.38 dBc/Hz, respectively. The frequency synthesizer including buffers consumes a total power of 70 mW from a 2 V power supply. The chip size is 1.5 × 1 mm2.

关键词： MOS phase locked loop frequency synthesizer multiple frequencies wideband phase noise

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激发传媒艺术创新活力助力文化强国建设

中国编辑 2025年第1期 11-16页

作者：胡智锋李天羽北京师范大学艺术与传媒学院北京电影学院视听传媒学院

在2035年建成文化强国战略目标的指引下，传媒艺术近年来依托主流价值指引发展方向、科技赋能助力融合创新以及理念革新促进创作出新取得了丰硕的发展成果。但在新形势下，传媒艺术仍然面临传媒艺术生态的不平衡性、技术赋能完全覆盖尚... 详细信息

在2035年建成文化强国战略目标的指引下，传媒艺术近年来依托主流价值指引发展方向、科技赋能助力融合创新以及理念革新促进创作出新取得了丰硕的发展成果。但在新形势下，传媒艺术仍然面临传媒艺术生态的不平衡性、技术赋能完全覆盖尚未实现以及市场波动波及传媒艺术创作的三重挑战。为应对挑战，传媒艺术不仅要锚定发展方略，也要坚定发展信心，更要从已有的经验与显现的问题中思考并总结应对之法。

关键词：传媒艺术文化强国建设科技赋能主流价值文化创新

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论一阶量词及其语义解释

外语学刊 2025年第1期 106-112页

作者：张力锋南京大学哲学系南京210023

一阶量词具有极大的普遍性,可以统一地处理由于论域变化造成的无限多日常量词。基于一阶语言公式的严格递归构造,重叠量化式归根结底可诉诸原子句和逻辑常项(特别是量词)的意义,得到准确的理解。代入解释挑战标准的量词解释,将量化语句... 详细信息

一阶量词具有极大的普遍性,可以统一地处理由于论域变化造成的无限多日常量词。基于一阶语言公式的严格递归构造,重叠量化式归根结底可诉诸原子句和逻辑常项(特别是量词)的意义,得到准确的理解。代入解释挑战标准的量词解释,将量化语句的真还原为相应去量化语句的代入实例的真,而代入实例被规定或设定为真未必是在存在论意义上,从而既能刻画一阶推理的有效性,又可确保量词作为逻辑常项的本体论中立性。但量化语句并未因代入量词的本体论中立而在语言实践中被剥夺存在含意,它的存在含意下沉至名字及命名关系;克里普克建构的代入量化语义佐证了以上论点,可以驳斥将代入量化看作一种特殊对象量化的误读,代入量化只表明量化语句的真值条件是某些代入实例为真,而不是将量化语句翻译或还原为那个代入实例。

关键词：量词满足代入解释本体论承诺真值条件名字

CrNbTiVAlx难熔高熵合金的组织、力学性能和高温氧化行为

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金属学报 2025年第1期 88-98页

作者：朱满张成许军锋坚增运惠增哲西安工业大学材料与化工学院

难熔高熵合金（RHEAs）具有高热稳定性、良好的高温力学性能和优异的高温抗氧化性能，有望作为一种潜在的耐高温结构材料使用。为了降低RHEAs密度、改善其高温抗氧化性能，本工作向CrNbTiV合金中添加Al元素，制备了一系列CrNbTiVAlx（x=... 详细信息

难熔高熵合金（RHEAs）具有高热稳定性、良好的高温力学性能和优异的高温抗氧化性能，有望作为一种潜在的耐高温结构材料使用。为了降低RHEAs密度、改善其高温抗氧化性能，本工作向CrNbTiV合金中添加Al元素，制备了一系列CrNbTiVAlx（x=0.25、0.5、0.75、1.0）难熔高熵合金。采用XRD、SEM、EDS和电子万能试验机等手段研究Al含量对CrNbTiV难熔高熵合金微观组织、力学性能和高温氧化行为的影响规律。结果表明，CrNbTiVAlx合金的微观组织由bcc、Laves和α-Ti相组成，bcc相以等轴晶形式分布。随着Al含量的增加，合金的密度逐渐减小，屈服强度由2037 MPa降低至1371 MPa；比屈服强度由CrNbTiVAl0.75合金的215.93 MPa·cm3/g增加至CrNbTiVAl0.25合金的323.33 MPa·cm3/g。CrNbTiVAlx合金在900℃氧化时的氧化动力学遵循抛物线规律，增加Al含量有利于提高合金的高温抗氧化性能。CrNbTiVAlx合金氧化后的氧化产物是由Al2O3、（CrNbTiVAl）O2和VOx组成的混合结构。当Al含量较低时，合金表面形成的连续、紧密的复杂氧化物（CrNbTiVAl）O2有效阻止了O2向基体内的扩散。随着Al含量的增加，复杂氧化物（CrNbTiVAl）O2含量减少，表面形成了更加致密、连续且细小的Al2O3氧化膜，从而显著提高了合金的高温抗氧化性能。

关键词：难熔高熵合金组织力学性能高温抗氧化性能

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