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1.
通过优化换能器拓扑结构和匹配网络设计,研制出f0=4.3 GHz,Δf-3 dB≥200 MHz,Δt=0.358μs的C波段声体微波延迟线。该产品的插入损耗约为-22 dB,直通抑制大于40 dB,三次渡越抑制大于28 dB,回波损耗约为-16 dB,产品综合性能指标优于国外同类产品。  相似文献   

2.
基于反馈式正弦波振荡器原理,设计出一款适合于UHF波段的高稳频型射频振荡器,本设计使用了高Q值选频技术,利用回路的谐振特性设计出多级的选频结构。振荡器输出频率范围:400 MHz~720 MHz,输出带宽大于300 MHz,属宽带射频振荡器。测试结果表明,在可用频段范围内,振荡器输出增益波动低于1 dB,输入驻波比VSWR<1.5 dB,输出驻波比VSWR<1.7 dB;中心频率f0=510 MHz时:频偏Δf=1 kHz处,相位噪声PN=-77.9 dBc/Hz;频偏Δf=10 kHz处,相位噪声PN=-95.8 dBc/Hz;频偏Δf=100 kHz处,相位噪声PN=-140.3 dBc/Hz;当频偏继续增加时,相位噪声呈指数下降。本设计可满足电视系统、无线对讲机系统、无线遥控系统等多种主流射频领域的应用要求。  相似文献   

3.
为了提高通信设备的性能,研制了高阻带的微波滤波器。该滤波器由5个高Q值的同轴介电陶瓷谐振器构成的带通滤波器。谐振器之间通过介电基片上的电容相互耦合。在装入外壳前,调整好每个谐振器的谐振频率和耦合电容,之后就不需要再调整,外壳上也没有可调零件,从而保证滤波器结构稳定,性能可靠。用εr=74的介电陶瓷制作出滤波器的性能为f0=982 MHz,Δf=10.9 MHzI,L=3.8 dB,阻带在f0±30 MHz处大于69 dB,远阻带衰减优于70 dB。  相似文献   

4.
利用Ansoft-HFSS仿真软件对微波介质滤波器进行建模及仿真,总结了结构参数对其电性能影响的变化规律,并提取了最优的器件结构参数.采用传统的电子陶瓷生产工艺制备样品,利用此规律指导器件的后期调试工作.结果表明,中心频率f0=2 493.0 MHz,插入损耗IL=1.539 dB,3 dB带宽BW3 dB=30.2 MHz,带内波动小于0.1 dB,在f0- 125 MHz外带外抑制Ls>45 dB;在f0 +125 MHz外Ls>65 dB,电压驻波比VSWR<1.2.测试结果与仿真结果吻合,验证了该规律的可行性和正确性.  相似文献   

5.
介绍了一种用于∑-ΔADC的低功耗运算放大器电路。该电路采用全差分折叠-共源共栅结构,采用0.35μm CMOS工艺实现,工作于3 V电源电压。仿真结果表明,该电路的动态范围为80 dB、直流增益68 dB、单位增益带宽6.8 MHz、功耗仅为87.5μW,适用于∑-ΔADC。  相似文献   

6.
带有输入、输出滤波器的前置放大器   总被引:1,自引:1,他引:0  
叙述了一种带有输入、输出滤波器的前置放大器的设计。在该滤波放大组件的设计中,主要解决了低插损、高隔离、小型化同轴滤波器和高增益、低噪声、温度性能稳定的放大器的优化设计,理论计算与实验结果相符合。主要研制结果:f_0=1 575.42MHz,G>39dB,NF<1.6dB,△f_(3dB)<30MHz,f_(30dB)<100MHz,f_(50dB)<200MHz。  相似文献   

7.
鲍景富 《电讯技术》2005,45(5):110-113
本文对3G的WCDMA中的ACS参数进行分析,解释33 dB的理由。并对实际电路的RF接收的ACS指标进行测试,设置测试的中心频率是2 110 MHz、2 140 MHz和2 170 MHz 3个高中低频率点,测得在偏离中心频率点 /-5 MHz的调制干扰信号值为-48 dBm到-42 dBm之间(BER=0.001时),可得幅度裕量在3.9 dB到9.2 dB之间,满足3GPP中的干扰信号-52 dBm电平要求。  相似文献   

8.
Q03噪声系数计量装置是按国际电工技术委员会(IEC)第147号标准研制的,用于计量600MHz和1GHz高频小功率低噪声晶体管的噪声系数F和最小噪声系数F_n,以便对晶体管的稳定性、低噪声和增益作出全面的质量评定,是研制和发展高频低噪声晶体管不可缺少的计量手段。本装置在测量高频小功率低噪声晶体管的噪声系数时,系统误差Δ_(SRSS)不大于0.2dB。总的误差(即(?),Δ_f为被测管的随机误差)在600MHz,而Δ_f<0.12dB时,不大于  相似文献   

9.
介绍了一种应用于无线通信领域的低电压、带有前馈结构的3阶4位单环Σ-Δ调制器。为了降低Σ-Δ调制器的功耗,跨导放大器采用了带宽展宽技术。采用TSMC 0.13 μm CMOS工艺对电路进行仿真,仿真结果显示,当工作电压为1.2 V、采样频率为64 MHz、过采样比为16、信号带宽为2 MHz时,电路的SNDR达81 dB,功耗仅为7.78 mW。  相似文献   

10.
本文报导采用两个换能器都进行了切趾加权和一多条耦合器结构的声表面波带通滤波器.滤波器的中心频率(f_0)为56MHz,相对带宽(△f_(3dB))为41%,矩形系数(3dB和40dB的带宽比)为1.41,带内波纹(△R)为±0.6dB,阻带抑制(SS)为-42dB和插入损耗(IL_(min))为27dB.为了使宽带滤波器具有很低的矩形系数,采用了衍射损耗补偿技术.改进的滤波器的性能参数为f_O=50MHz,△f_(3dB)=47.6%,矩形系数(3dB和30dB的带宽比)=1.12,△R=±0.7dB,SS=-37dB和IL_(min)=31dB.  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

15.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

16.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

17.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

18.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.  相似文献   

19.
Call for Papers     
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks  相似文献   

20.
正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first  相似文献   

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