基于低相噪的Ku波段频率合成器研究

频率合成器主要以精准的传输方式以及稳定的传输形态进行信号传输。文章以Ku波段低相噪频率合成器为主要研究对象,针对频率合成器的技术内容进行多角度、多层次、多维度的分析和论述,结合笔者在频率合成器领域的科研经验,提出一系列与Ku波段低相噪频率合成器相关的研究内容。     

基于雷达信号模拟器的Ku波段宽带跳变源的设计

文章采用DDS驱动PLL的方式,实现了一种能完全覆盖Ku波段的宽带小步进低相位噪声低杂散频率合成器的设计,同时对DDS PLL频率合成器的输出特性进行了理论分析,并通过实验进行了验证.最终我们研制出了输出频率为12-18GHz的频综系统,步进为1MHz,相位噪声优于-90 dBc/Hz@10kHz,杂散优于-50dBc.     

超宽带频率合成器设计

本文介绍了一种用DDs激励PLL的超宽带X波段频率合成器的设计方案,给出了方案选择和具体芯片设计,对产品进行了指标测试,结果表明该X波段频率合成器带宽可以达到4000MHz,输出相位噪声优于-80dBc／Hz@10kHz、频率分辨力达0．1MHz。     

Ku波段四路径向功率合成器的设计与实现

介绍了径向合成技术,并对径向波导的电磁场进行了分析,提出了一种新型功率合成器结构。并对基于径向合成技术的Ku波段四路功率合成器的结构进行设计,利用CST软件对该合成器的表面电流分布、能量密度、插损和驻波特性进行仿真。仿真结果表明,基于径向合成技术的Ku波段四路功率合成器的插损和驻波特性优良,完全适用于需求输出大功率的Ku波段的功放组件,突破了工程化应用的技术瓶颈。     

高抗振X波段低相噪频率合成器

介绍了一个X波段频率合成器的设计,该频率合成器通过采用混频锁相环的方式实现,本振锁相环输出8 GHz的信号,作为混频器的本振信号,混频环最终输出信号为8.5~9.0 GHz,输出静态相位噪声为-93 dBc/Hz@1 kHz offset。此外,还研制了一种小型化的隔振器来降低振动对晶振的影响,对环路也采取了相应的减振措施,提高了该合成器在振动下的相位噪声,振动环境下相位噪声为-90 dBc/Hz@1 kHz offset。     

基于DDS激励PLL方式的Ku波段频率源

采用Ku波段压控整荡器(VCO)HMC632,结合直接数字式频率合成器(DDS)AD9850、鉴相器ADF4107和运算放大器AD820设计了一款基于DDS激励PLL方式的Ku波段频率源。测试结果表明,该频率源在输出频率范围为15~15.5GHz,跳频时间间隔为20μs时的锁定时间为2μs,杂散小于-60dBc,相位噪声小于-70dBc/Hz@10kHz,输出功率大于7dBm。设计思路简洁,电路结构简单。     

某机载抗振捷变频频综器设计

设计了1种用于某机载电子设备上的捷变频频率综合器。该合成器采用快捕、隔振技术以及数字锁相和谐波混频技术,在很小的体积内实现了合成器的低相噪、捷变频和抗振等性能指标。测试结果为:输出频率Ku波段,带宽480 MHz,跳频点数49点,相噪优于-96dBc/Hz/1kHz,杂波抑制优于-70 dBc,捷变频时间小于50μs。     

双耦合跨导增强型低功耗压控振荡器

设计了一种工作于Ku波段和Ka波段的新型电容电感压控振荡器(LC VCO),具有低功耗和低相位噪声的优点。Ku波段的信号由交叉耦合LC VCO产生,在此基础上利用PMOS push-push倍频器结构,将信号频率由Ku波段扩展到Ka波段。采用互补型交叉耦合对结构,通过电流复用技术,提高信号的输出摆幅。同时该结构通过电容分裂技术和栅极漏极阻抗平衡技术,降低了功耗和相位噪声。该双频段VCO芯片基于0.13μm CMOS工艺实现,尺寸为0.88 mm×0.64 mm。测试结果表明,在1.25 V电源电压下,该VCO的功耗为2.25 mW。14.53 GHz时,该VCO在偏移中心频率1 MHz和10 MHz处的输出相位噪声分别为-115.3 dBc/Hz和-134.8 dBc/Hz, 29.08 GHz时的输出相位噪声分别为-109.67 dBc/Hz和-129.23 dBc/Hz。     

Ku波段介质锁相抗振频率源研制

提出了一种混频介质锁相的方案,对Ku波段的发射信号进行一次混频锁相得到Ku波段的本振信号,实现了本振信号与发射信号的相位同步。电路设计采用了低噪底鉴相芯片和自主设计的低相噪Ku波段介质压控振荡器(DRVCO)。结构设计中充分考虑抗振动性能,并用ANSYS软件对结构进行力学仿真,达到很好的抗振动效果,组件外形尺寸为110mm×65mm×13mm。测试结果表明,静态下该Ku波段频率源输出功率12dBm,杂波抑制比≥70dBc,相位噪声-91dBc/Hz/@1kHz,-105dBc/Hz@10kHz;振动条件下1kHz、10kHz处相位噪声恶化不超过3dB。     

读者信箱

问:双本振单输出C波段高频头,为何有5150和5750两个频率?答:不管是C波段卫星信号还是Ku波段卫星信号,在高频头上都要进行变频处理,变频后输出950～2150(MHz)范围的中频信号。一般C波段信号的下行频率为3.7～4.2GHz,如果只     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

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.     

Cost-effective test solutions for smart card and other integrated flash applications

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.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

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.     

An improved parallel thinning algorithm with two subiterations

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.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

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.     

Study of waveguide coupling efficiency in hybrid silicon lasers

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.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

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.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

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.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

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