Decentralized Spectrum and Radio Resource Management Enabled by an On-demand Cognitive Pilo
物探专业术语中英文对照
物探专业术语中英文对照lunar tide 太阴潮solar tide 太阳潮turbulence 湍流spectrum of turbulence 湍流谱turbulent diffusion 湍流扩散turbulent dissipation 湍流耗散turbulent exchange 湍流交换turbulent mixing 湍流混合twilight 曙暮光wind shear 风切变yield function 产额函数zonal circulation 纬向环流zonal wind 纬向风airglow 气辉MST radar MST雷达，对流层、平流层、中层大气探测雷达。
aeronomy 高空大气学deviative absorption 偏移吸收non-deviative absorption 非偏移吸收after-effect of [magnetic] storm 磁暴后效Chapman layer 查普曼层Appleton anomaly 阿普尔顿异常equatorial anomaly 赤道异常winter anomaly 冬季异常magneto-ionic theory 磁离子理论buoyancy frequency 浮力频率D - region Ｄ区E - region Ｅ区F - region Ｆ区F1 layer Ｆ1层F1 ledge Ｆ1缘F2 layer Ｆ2层Chapman production function 查普曼生成函数Cowling conductivity 柯林电导率Pedersen conductivity 彼得森电导率Hall conductivity 霍尔电导率direct conductivity 直接电导率cosmic radio noise 宇宙射电噪声riometer 宇宙噪声吸收仪critical frequency 临界频率dissociative recombination 离解性复合dynamo region 发电机区evanescent wave 消散波fade 衰落fadeout, blackout [短波通讯]中断ordinary wave 寻常波extraordinary wave 非寻常波Faraday rotation 法拉第旋转field-aligned irregularity 场向不规则结构Harang discontinuity 哈朗间断impedance probe 阻抗探针incoherent scattering radar 非相干散射雷达ionospheric storm 电离层暴ionosonde 电离层测高仪virtual height 虚高true height 真高digisonde 数字式测高仪ionogram 电离图polar cap absorption, PCA 极盖吸收sudden ionospheric disturbance, SID 突发电离层骚扰spread F 扩展 Fsporadic E 散见 E 层top-side sounder 顶视探测仪bottom-side sounder 底视探测仪travelling ionospheric disturbance, TID 电离层行扰short wave fadeout, SWF 短波突然衰落sudden frequency deviation, SFD [短波]频率急偏sudden phase anomaly, SPA 突发相位异常characteristic wave 特征波cross-modulation 交叉调制total electron content, TEC 电子总含量ambipolar diffusion 双极扩散eclipse effect [日]食效应skip distance 跳距outer space 外层空间interplanetary space 行星际空间interstellar space [恒]星际空间deep space 深空solar-terrestrial space 日地空间solar-terrestrial physics 日地物理学one-hop propagation 一跳传播quasi-transverse propagation 准横传播quasi-longitudinal propagation 准纵传播maximum usable frequency, MUF 最大可用频率geomagnetism 地磁[学] main field 主磁场inclination, dip angle 磁倾角declination 磁偏角agonic line 零偏线aclinic line 零倾线magnetic isoclinic line 等磁倾线magnetic chart 磁图isomagnetic chart 等磁图isomagnetic line 等磁强线isoporic line, isopore 等年变线magnetic isoanomalous line 等磁异常线geomagnetic pole 地磁极dip pole 磁倾极magnetic local time 磁地方时magnetic dipole time 磁偶极时central dipole 中心偶极子dipole coordinate 偶极子坐标corrected geomagnetic coordinate 修正地磁坐标north magnetic pole 磁北极south magnetic pole 磁南极invariant latitude 不变纬度dip equator 倾角赤道eccentric dipole 偏心偶极子magnetogram 磁照图magnetically quiet day, q 磁静日magnetically disturbed day, d 磁扰日secular variation 长期变化solar daily variation, S 太阳日变化disturbed daily variation, Sd 扰日日变化storm-time variation, Dst 暴时变化magnetic disturbance 磁扰magnetic bay 磁湾扰magnetic crochet 磁钩扰magnetic storm 磁暴gradual commencement [magnetic] storm 缓始磁暴sudden commencement [magnetic] storm 急始磁暴sudden commencement 急始initial phase 初相main phase 主相recovery phase 恢复相magnetic substorm 磁亚暴expansive phase 膨胀相equivalent current system 等效电流系internal field 内源场external field 外源场aurora 极光aurora australis 南极光aurora borealis 北极光auroral oval 极光卵形环auroral belt 极光带subauroral zone 亚极光带Alfvēen layer 阿尔文层cleft, cusp 极隙pseudo-trapped particle 假捕获粒子radiation belt, Van Allen belt 辐射带又称“范艾伦带”。
核磁共振中常用的英文缩写和中文名称
NMR中常用的英文缩写和中文名称收集了一些NMR中常用的英文缩写,译出其中文名称,供初学者参考,不妥之处请指出,也请继续添加.相关附件NMR中常用的英文缩写和中文名称APT Attached Proton Test 质子连接实验ASIS Aromatic Solvent Induced Shift 芳香溶剂诱导位移BBDR Broad Band Double Resonance 宽带双共振BIRD Bilinear Rotation Decoupling 双线性旋转去偶（脉冲）COLOC Correlated Spectroscopy for Long Range Coupling 远程偶合相关谱COSY ( Homonuclear chemical shift ) COrrelation SpectroscopY （同核化学位移）相关谱CP Cross Polarization 交叉极化CP/MAS Cross Polarization / Magic Angle Spinning 交叉极化魔角自旋CSA Chemical Shift Anisotropy 化学位移各向异性CSCM Chemical Shift Correlation Map 化学位移相关图CW continuous wave 连续波DD Dipole-Dipole 偶极-偶极DECSY Double-quantum Echo Correlated Spectroscopy 双量子回波相关谱DEPT Distortionless Enhancement by Polarization Transfer 无畸变极化转移增强2DFTS two Dimensional FT Spectroscopy 二维傅立叶变换谱DNMR Dynamic NMR 动态NMRDNP Dynamic Nuclear Polarization 动态核极化DQ(C) Double Quantum (Coherence) 双量子（相干）DQD Digital Quadrature Detection 数字正交检测DQF Double Quantum Filter 双量子滤波DQF-COSY Double Quantum Filtered COSY 双量子滤波COSYDRDS Double Resonance Difference Spectroscopy 双共振差谱EXSY Exchange Spectroscopy 交换谱FFT Fast Fourier Transformation 快速傅立叶变换FID Free Induction Decay 自由诱导衰减H,C-COSY 1H,13C chemical-shift COrrelation SpectroscopY 1H,13C化学位移相关谱H,X-COSY 1H,X-nucleus chemical-shift COrrelation SpectroscopY 1H,X-核化学位移相关谱HETCOR Heteronuclear Correlation Spectroscopy 异核相关谱HMBC Heteronuclear Multiple-Bond Correlation 异核多键相关HMQC Heteronuclear Multiple Quantum Coherence异核多量子相干HOESY Heteronuclear Overhauser Effect Spectroscopy 异核Overhause效应谱HOHAHA Homonuclear Hartmann-Hahn spectroscopy 同核Hartmann-Hahn谱HR High Resolution 高分辨HSQC Heteronuclear Single Quantum Coherence 异核单量子相干INADEQUATE Incredible Natural Abundance Double Quantum Transfer Experiment 稀核双量子转移实验（简称双量子实验，或双量子谱）INDOR Internuclear Double Resonance 核间双共振INEPT Insensitive Nuclei Enhanced by Polarization 非灵敏核极化转移增强INVERSE H,X correlation via 1H detection 检测1H的H,X核相关IR Inversion-Recovery 反（翻）转回复JRES J-resolved spectroscopy J-分解谱LIS Lanthanide (chemical shift reagent ) Induced Shift 镧系（化学位移试剂）诱导位移LSR Lanthanide Shift Reagent 镧系位移试剂MAS Magic-Angle Spinning 魔角自旋MQ(C) Multiple-Quantum ( Coherence ) 多量子（相干）MQF Multiple-Quantum Filter 多量子滤波MQMAS Multiple-Quantum Magic-Angle Spinning 多量子魔角自旋MQS Multi Quantum Spectroscopy 多量子谱NMR Nuclear Magnetic Resonance 核磁共振NOE Nuclear Overhauser Effect 核Overhauser效应（NOE）NOESY Nuclear Overhauser Effect Spectroscopy 二维NOE谱NQR Nuclear Quadrupole Resonance 核四极共振PFG Pulsed Gradient Field 脉冲梯度场PGSE Pulsed Gradient Spin Echo 脉冲梯度自旋回波PRFT Partially Relaxed Fourier Transform 部分弛豫傅立叶变换PSD Phase-sensitive Detection 相敏检测PW Pulse Width 脉宽RCT Relayed Coherence Transfer 接力相干转移RECSY Multistep Relayed Coherence Spectroscopy 多步接力相干谱REDOR Rotational Echo Double Resonance 旋转回波双共振RELAY Relayed Correlation Spectroscopy 接力相关谱RF Radio Frequency 射频ROESY Rotating Frame Overhauser Effect Spectroscopy 旋转坐标系NOE谱ROTO ROESY-TOCSY Relay ROESY-TOCSY 接力谱SC Scalar Coupling 标量偶合SDDS Spin Decoupling Difference Spectroscopy 自旋去偶差谱SE Spin Echo 自旋回波SECSY Spin-Echo Correlated Spectroscopy自旋回波相关谱SEDOR Spin Echo Double Resonance 自旋回波双共振SEFT Spin-Echo Fourier Transform Spectroscopy (with J modulation) （J-调制）自旋回波傅立叶变换谱SELINCOR Selective Inverse Correlation 选择性反相关SELINQUATE Selective INADEQUA TE 选择性双量子（实验）SFORD Single Frequency Off-Resonance Decoupling 单频偏共振去偶SNR or S/N Signal-to-noise Ratio 信/ 燥比SQF Single-Quantum Filter 单量子滤波SR Saturation-Recovery 饱和恢复TCF Time Correlation Function 时间相关涵数TOCSY Total Correlation Spectroscopy 全（总）相关谱TORO TOCSY-ROESY Relay TOCSY-ROESY接力TQF Triple-Quantum Filter 三量子滤波WALTZ-16 A broadband decoupling sequence 宽带去偶序列WATERGATE Water suppression pulse sequence 水峰压制脉冲序列WEFT Water Eliminated Fourier Transform 水峰消除傅立叶变换ZQ(C) Zero-Quantum (Coherence) 零量子相干ZQF Zero-Quantum Filter 零量子滤波T1 Longitudinal (spin-lattice) relaxation time for MZ 纵向（自旋-晶格）弛豫时间T2 Transverse (spin-spin) relaxation time for Mxy 横向（自旋-自旋）弛豫时间tm mixing time 混合时间τ c rotational correlation time 旋转相关时间。
表面增强衰减全反射红外光谱英文
表面增强衰减全反射红外光谱英文Alright, here's a piece of writing on Surface-Enhanced Attenuated Total Reflection Infrared Spectroscopy (SEATR-IR) in an informal and conversational tone, while adhering tothe given requirements:So, have you ever heard of SEATR-IR? It's like thiscool party trick in the world of spectroscopy. It takes infrared light and makes it dance on a surface, but notjust any surface. This one's enhanced! It's like adding a little sparkle to your outfit, but for molecules.Yeah, the science part is that it uses total reflection to capture the vibrations of molecules. But don't get me wrong, it's not like a mirror reflecting light—it's more like a whisper-loud conversation between molecules andlight waves. And when you enhance that surface, it's like adding a megaphone to the mix.Imagine going to a concert and being able to hear everynote, every breath, every nuance. That's what SEATR-IR does for molecules. It gives us a super-detailed view of what's happening on that surface, like a high-def camera zoomingin on a tiny dance floor.And the cool thing is, this isn't just for show. Scientists use it to understand reactions, to figure.。
傅里叶红外光谱的英文
傅里叶红外光谱的英文傅里叶红外光谱的英文I. IntroductionInfrared spectroscopy is a common analytical method used for studying the chemical properties of a sample. Fourier transform infrared spectroscopy (FTIR), also known as Fourier transform infrared (FTIR) analysis, is a type of infrared spectroscopy that uses a Fourier transform to obtain the spectral information. In this article, we will discuss the English terminology used for FTIR.II. Basic Terminology1. Infrared spectrum: a representation of the absorption or transmission of infrared radiation as a function of wavelength or frequency2. Spectral range: the range of wavelengths or frequencies measured in the infrared spectrum3. Wavenumber: the reciprocal of wavelength, measured in cm-1 in the FTIR spectrum4. Absorbance: the logarithm of the ratio of the incident radiation to the transmitted radiation, measured in the FTIR spectrum5. Peak: a point on the FTIR spectrum that corresponds to a specific vibrational mode of the sample6. Baseline: the absorption background in the FTIR spectrumIII. Sample PreparationBefore performing FTIR analysis, the sample must be prepared in the formof a thin film or powder to ensure uniformity of the sample.IV. InstrumentationFTIR analysis requires a Fourier transform infrared spectrometer, which consists of a source, interferometer, and detector. The sample is placed in the path of the infrared beam generated by the source and the transmitted or absorbed radiation is measured by the detector. The interferometer is used to obtain the interferogram, which is then transformed into the FTIR spectrum.V. ApplicationsFTIR is used in various fields such as chemistry, pharmaceuticals, and material science. It is commonly used for the identification of unknown compounds, characterization of functional groups, and monitoring of chemical reactions.VI. ConclusionFTIR analysis is a powerful technique for studying the chemical properties of a sample. Understanding the basic terminology and instrumentation used in FTIR is essential for accurate interpretation of the spectral data.。
基于残差自编码器的电磁频谱地图构建方法
doi:10.3969/j.issn.1003-3114.2023.02.007引用格式:张晗,韩宇,姜航,等.基于残差自编码器的电磁频谱地图构建方法[J].无线电通信技术,2023,49(2):255-261.[ZHANG Han,HAN Yu,JIANG Hang,et al.Electromagnetic Spectrum Map Construction Method Based on Residual Autoencoder [J].Radio Communications Technology,2023,49(2):255-261.]基于残差自编码器的电磁频谱地图构建方法张㊀晗,韩㊀宇,姜㊀航,付江志,林㊀云∗(哈尔滨工程大学信息与通信工程学院,黑龙江哈尔滨150001)摘㊀要:频谱地图是一种表征区域内功率谱密度(Power Spectral Density,PSD)空间分布的可视化方法,在实现频谱资源空间复用等方面具有重要作用㊂针对实际复杂场景下频谱地图构建精度低的问题,提出了一种基于残差自编码器的频谱地图构建方法,通过添加残差连接使编码器的信息可以直接映射到解码器相应部分,以提高频谱地图构建中的网络收敛性能并降低误差㊂仿真实验结果表明,所提出的方法相比于基于传统插值方法和自编码器模型具有更好的性能,在0.01采样率下其构建误差降低了9.7%㊂关键词:频谱地图;残差自编码器;深度学习中图分类号:TN919.23㊀㊀㊀文献标志码:A㊀㊀㊀开放科学(资源服务)标识码(OSID):文章编号:1003-3114(2023)02-0255-07Electromagnetic Spectrum Map Construction Method Based onResidual AutoencoderZHANG Han,HAN Yu,JIANG Hang,FU Jiangzhi,LIN Yun ∗(College of Information and Communication Engineering,Harbin Engineering University,Harbin 150001,China)Abstract :Spectrum map is a visualization method to characterize the spatial distribution of Power Spectral Density (PSD)in aregion,and plays an important role in spatial reuse of spectrum resources.To solve the problem of low accuracy of spectrum map construc-tion in actual complex scenes,a spectrum map construction method based on residual autoencoder is proposed.By adding residual connec-tions,the information of the encoder can be directly mapped to the corresponding part of the decoder,so as to improve network convergence performance and reduce the error in spectrum map construction.Simulation results show that the proposed method has better performance than the traditional interpolation method and autoencoder model.And its construction error is reduced by 9.7%at 0.01sampling rate.Keywords :spectrum map;residual autoencoder;deep learning收稿日期:2022-12-07基金项目:国家自然科学基金(61771154)Foundation Item :National Natural Science Foundation of China(61771154)0 引言近年来,随着通信技术的快速发展和各种新型通信设备的应用部署[1],日益稀缺的电磁频谱资源和当前粗放的频谱分配方式及其导致的频谱资源利用率低下问题之间的矛盾愈发突出[2]㊂电磁频谱作为一种有限的国家重要战略资源,当前迫切需要对其进行合理分配和精细化管理以提高电磁空间的频谱利用率[3-4]㊂电磁频谱地图作为一种频谱态势的可视化手段,其精准构建方法受到学者们的广泛关注[5]㊂电磁频谱地图(Spectrum Map)又称无线电地图(Radio Map)或无线电环境地图(Radio Environment Map),是一种从时间㊁频率㊁空间以及能量等角度精确表征区域空间中电磁频谱态势分布的可视化方法[6]㊂它通过映射区域空间中功率谱密度(Power Spectral Density,PSD)等信息的分布来反映频谱态势的分布情况㊂通过实时构建的电磁频谱地图,可以及时发现频谱空洞,定位 黑广播 伪基站 等非法用频设备,在完善频谱空间精细分配与管理㊁提高电磁环境监管治理水平等方面具有广阔的应用场景[7]㊂受限于数据获取在空间上的稀疏性和不均匀性,如何利用残缺数据构建完整的频谱地图一直是频谱地图构建中的重要问题㊂对于频谱地图的补全构建方法,夏海洋等人[4]将其总结为参数构建法㊁空间插值构建法以及混合构建法3种类别㊂参数构建法通常使用发射机位置㊁发射参数等先验信息构建频谱地图[8]㊂空间插值法常用的算法包括最邻近法(Nearest Neighbor,NN)[9]㊁径向基函数法(Rad-ial Basis Function,RBF)[10]以及克里金法(Krig-ing)[11]等㊂空间插值法不依赖于其他先验知识,仅使用获取的离散数据间的空间相关性来估计空缺位置的监测数值㊂一般来说,参数构建法在先验信息丰富的场景下可以得到更高的建模精度,但在没有或先验信息较少的场景下性能会急剧下降㊂考虑到一般实际场景中,先验信息获取困难,所以空间插值法是当前最流行的方法㊂混合构建法则是上述两种方法的结合,可以在没有或先验信息较少的情况下获得更高精度的结果[12]㊂近几年,随着深度学习技术的快速发展和在多个领域特别是图像生成领域的广泛应用㊂一些研究者参考图像生成的方法,开始尝试使用一些基于深度学习的频谱地图构建方法㊂胡田钰等人[13]使用生成对抗网络实现来三维空间的频谱态势补全,Imai 等人[14]提出利用卷积神经网络进行无线电传播预测,Teganya 等人[15]使用深度自编码器学习传播的空间结果并进行无线电地图的预测㊂Saito 等人[16]通过使用路径损失回归将空间插值问题转化为阴影调整问题,并使用编码解码模型和一种新的渐进学习的训练方法㊂本文提出了一种残差自编码器的频谱地图的构建,在模型中添加残差连接以提高模型的收敛速度并降低预测误差㊂然后,参考图像生成领域的工作[17],在输入中添加一个二进制的掩码用以区分输入缺失位置和测量值㊂最后,通过一个仿真实验来验证提出的残差自编码器与一般自编码器以及传统插值相比的性能优势㊂1 电磁频谱地图构建系统模型本文主要研究和讨论基于PSD 的电磁频谱地图构建问题㊂一般来说,为了便于理解和实现,当前的频谱地图通常是基于单频的PSD 构建的,所以本文后续只考虑单频PSD 的估计问题㊂定义如下场景:在一个固定的地理区域χ中分布着若干个工作在同一特点频点的辐射源S ㊂设Υs (f )表示第s 个辐射源的发射PSD,H s (x ,f )表示第s 个辐射源与空间位置x 处具有各项同性天线的接收器之间的信道频率响应㊂假设在较短时间内Υs (f )和H s (x ,f )是时不变的,且不同辐射源信号之间是不相关的,则在x 处的接收PSD 总和可以表示为:Ψ(x ,f )=ðΥs(f )|H s (x ,f )|2+υ(x ,f ),(1)式中,υ(x ,f )表示由热噪声㊁背景辐射噪声以及其他原因造成的干扰㊂同时,空间中分布着一定数量的装备各项同性天线的接收设备,在不同的位置通过周期图或者频谱分析的方式感知PSD 测量值Ψ~(x n ,f ),并将测量值发送至融合中心㊂融合中心通过n 个位置的PSD 测量值,估计和映射在空间中所有位置的PSD 值Ψ(x ,f )㊂整体的电磁频谱地图构建框架如图1所示㊂图1㊀电磁频谱地图构建框架Fig.1㊀Construction framework of electromagnetic spectrummap㊀㊀关于传感器的分布问题,有些研究成果为进一步节省成本,使用移动监测的策略㊂然而移动监测本身需要一定的监测时长,在频谱态势变化敏捷的场景下难以取得良好的效果;由于监测路径是连续的,会进一步加重监测数据在空间上分布不均匀的问题㊂所以本文从通用性的角度出发,仍考虑分布式监测传感器的策略㊂现有数据驱动的频谱地图构建方法通常依赖于某种插值算法㊂然而这些算法无法从经验中学习,只能通过数据自身的规律性完成频谱地图的补全㊂显然,这种方法在场景较为简单㊁辐射源数量较少㊁传感器分布广泛的情况下可以取得不错的结果㊂但在一些复杂场景下,特别是传感器分布较为稀疏时,插值算法难以准确地估计一些敏感位置的频谱PSD,导致插值算法在一些细节上估计误差偏高㊂随着机器学习,特别是深度学习的发展,其强大的学习和拟合能力被看作是提高频谱地图构建的有效方法㊂因此,一些学者提出使用一些基于深度学习的图像补全的方法实现电磁频谱地图的构建[16]㊂本文基于上述思路,设计了一种残差自编码器用于频谱地图的构建㊂2㊀频谱地图构建方法2.1㊀基于补全自编码器的频谱地图构建基于深度学习的频谱地图构建的总体思路是通过构建一个函数pω来处理缺失的数据㊂也就是说,将整个观测空间离散为一个网格张量,已知部分监测位置的观测值Ψ~(x i,f),其中x iɪΩ,表示监测传感器的部署位置㊂希望网络输入已知观测值Ψ~(x i,f),输出完整的频谱地图Ψ(x,f)㊂因此网络的训练如下: minimize1TðT t=1 Ψt-pω(Ψ~t) 2F,(2)式中,T代表输入的总观测时长,pω(Ψ~t)为基于位于Ω的观测数据而生成的完整频谱地图数据㊂自编码器网络是一种在图像生成领域广泛应用的无监督网络架构[18]㊂自编码器由一个编码器和一个解码器串联组成㊂其编码器的输出一般被认为是输入图像或数据的潜在特征矢量,其维度通常远低于输入数据维度㊂自编码器的工作原理就是通过训练使得解码器重建的输出能够完美地接近于编码器的输入,基于编码器输出的特征矢量,自编码器可以被应用于数据降维㊁图像降噪以及异常检测等任务㊂补全自编码器同样遵循自编码器的模型架构,不同在于其输入缺失的张量数据,而输出完整的张量[18]㊂在实际操作中,通常使用0值表示缺失部分组成一个完整张量作为模型的输入㊂尽管如此,基于深度学习的模型仍没有考虑Ω㊂也就是说网络无法区分测量值与填充值,因此填充性能较差㊂本文参考了图像修复领域的经验,添加了一个二进制的掩码作为输入的另一个维度㊂该掩码直接使用1和0表征实际观测位置和缺失部分,有利于模型更好地训练㊂2.2㊀残差自编码器模型架构本文在自编码器的基础上添加了残差连接,构建一个残差自编码器,其模型架构如图2所示㊂图2㊀残差自编码器模型框架Fig.2㊀Framework of residual autoencodermodel㊀㊀在图2所示的模型中,使用了10个卷积核大小为3ˑ3的卷积层来构建编码器,和10个与之相对应的反卷积层(转置卷积)构建解码器,也就是说本文使用的模型是一个全卷积的自编码器,其中所有的卷积和反卷积层都使用Leaky ReLU函数作为激活函数㊂相比于基于全连接层的自编码器模型,基于卷积的自编码器模型参数更少,可以大幅降低训练所需的数据量,同时卷积也更适合学习频谱地图的空间信息㊂在实际操作中,使用池化层和插值来分别实现模型中的上采样和下采样㊂最后,在编码器和解码器之间添加了3个残差连接,使编码器的信息可以跨层映射到解码器,从而允许梯度直接流向更浅的层,加快模型的收敛速度㊂模型的输入是一个由残缺的频谱监测数据以及表征了观测数据位置的二进制编码张量所组成的大小为N xˑN yˑ2的输入张量㊂其中N x与N y为输入残缺数据张量的长宽㊂模型的输出为补全的完整频谱地图张量,其大小为N xˑN yˑ1㊂3㊀仿真实验3.1㊀仿真数据集构建在基于深度学习模型或者其他数据驱动的频谱地图构建方法中,一个不可避免的问题是需要大量的数据进行训练㊂然而在实际场景中获取完整的频谱地图数据十分困难且成本过高,所以研究者们通常使用一些基于传播模型生成的仿真数据㊂许多研究成果表明,使用仿真数据构建的模型在真实场景中同样可以起到较好的补全效果㊂本文使用了一个开源的频谱地图数据集㊂该数据集使用Remcom公司的Wireless InSite软件,针对遮掩物较多㊁电波传播环境较为复杂的 城市峡谷 场景生成㊂数据集中应用了弗吉尼亚州罗斯林市中心的三维地图,这是一个边长约700m的正方形区域,然后结合了射线追踪(Ray Tracing,RT)算法㊂具体来说,采用弹跳射线法(Shooting and Bouncing Ray)进行仿真,在仿真参数中,最大反射和衍射次数分别设置为6和2㊂该数据集可以被视为实测数据集的一个有效的替代品㊂该数据集的网格分辨率为3m,每张原始频谱地图的大小为245mˑ245m㊂实验中,通过在原始频谱地图上选取随机位置构建大量32mˑ32m的张量数据,即长宽约为100mˑ100m的频谱地图用于仿真实验㊂图3展示了一个随机抽取的用于实验的样本地图㊂需要注意的是,实验中所有的频谱地图数据均使用对数单位dBmW(简称dBm),取代了自然功率单位,这样可以避免数据分布不均所带来的性能损失㊂在新生成的频谱地图数据中,随机抽取一定比例的观测位置作为已知数据,原始数据集共包含频率为1400MHz的42张完整频谱地图,在实验中,使用前40张地图生成的数据进行模型训练,后两张地图生成的数据用于测试㊂基于上节所介绍的输入数据构建方法,构建了5000个训练样本用于残差自编码器的训练,并使用两个全新没有训练过的地图构建了1000个测试样本用于评估模型的性能㊂图3㊀生成仿真数据集示例Fig.3㊀Generate simulation dataset example3.2㊀仿真结果与分析为了验证本文提出方法的有效性,将本文使用的残差自编码器模型与传统的自编码器模型以及3种常用的插值算法进行比较㊂尽可能调整不同模型的参数使其获得最佳性能㊂所有对比模型的具体参数设置如下:①传统自编码器模型,与本文使用的残差自编码器模型基本一致,包含10个卷积层构建的编码器与10个反卷积层构建的解码器组成,主要区别为不包含残差连接;②克里金算法,使用正则化参数为10-5,高速径向基函数的宽度参数σ被设置为采集测量值的两点之间平均距离的5倍;③核学习算法,包括20个拉普拉斯核,使用正则化参数为10-4;④K最邻接算法,作为最基础的频谱地图构建方法,设置了K=5㊂实验中的深度学习网络均基于TensorFlow框架搭建,并使用Adam优化器进行训练,学习率被设置为10-5,batch size大小为16,所有模型训练100个epoch㊂使用均方根误差(RMSE)作为模型性能的指标:RMSE= Ψ-Ψ^ 2FN x N y,(3)式中,Ψ为频谱地图的真实值,Ψ^为估计值㊂基于测试集中的1000个样本评估模型在不同采样率下的补全误差水平㊂比较了上述所有基线模型和本文使用的参差自编码器在0.01~0.20采样率条件下的性能,结果如图4所示㊂由于本文使用了一个接近真实数据的复杂的实验数据集,所以其预测误差指标对比于一些使用简单仿真数据集的文献会偏高㊂由图4可以看出,本文使用的残差自编码器在0.20的采样率下均方根误差为2.86dB,即使在0.01的低采样率下也可以达到7.91dB㊂相较于其他模型和算法,本文所使用的模型几乎在每种采样率下都取得了最好的性能㊂其次是传统的自编码器模型,在低采样率下与残差自编码器性能相差无几,随着采样率的升高,其性能水平被逐渐拉开差距㊂图4㊀残差自编码器与其他基线模型性能对比Fig.4㊀Performance comparison between residualautoencoder and other baseline models图5展示了在0.1的采样率条件下对于测试样本集中的某一样本的补全结果㊂由图5可以看出,本文提出使用的基于残差自编码器的模型取得了最低的补全RMSE误差㊂同时,提出的残差自编码器可以较高程度地还原真实数据中由于城市场景中复杂的信道传播效应等产生的纹路细节;其次是传统自编码器模型,其在整体上基本还原了真实数据的主要特征,而其他基于传统插值算法的方法则分别出现了不同程度的失真,补全效果较差㊂(a)真实数据㊀㊀㊀㊀(b)残差自编码器结果RMSE=1.450129㊀㊀㊀㊀(c)传统自编码器结果RMSE=3.009530 (d)克里金插值法结果RMSE=4.527919㊀㊀㊀㊀(e)核学学算法结果RMSE=3.461993㊀㊀㊀㊀(f)K最邻接算法结果RMSE=3.914541图5㊀0.1采样率条件下不同模型补全效果对比Fig.5㊀Comparison of completion effects of different models at0.1sampling rate㊀㊀图6展示了残差自编码器与传统自编码器在100个epoch下的训练损失的对比结果㊂由图6可以看出,在两种模型架构和超参数基本一致的条件下,添加了残差连接的补全模型明显优于原始模型,同时收敛速度更快,该结果说明添加残差连接的策略是有效的㊂图6㊀残差自编码器与传统自编码器训练损失对比Fig.6㊀Comparison of training loss between residualautoencoder and traditional autoencoder4 结论针对实际复杂场景下频谱地图生成精度低的问题,本文构建了一个基于残差自编码器的补全模型用于学习无线电信道传播的空间结构,实现频谱地图的高精度构建㊂基于自编码器的深度学习方法可以很好地拟合数据,而添加残差连接的方法又进一步降低了估计误差㊂在一个接近真实场景的仿真数据集上进行对比试验,结果证明本文提出的残差自编码器模型对比其他基线模型具有更好的补全精度㊂然而,基于数据驱动的频谱地图补全方法始终受大量数据获取问题的困扰,在实际场景应用受限㊂未来的工作将围绕通过迁移缓解大量训练数据获取难的问题展开㊂参考文献[1]㊀张思成,林云,涂涯,等.基于轻量级深度神经网络的电磁信号调制识别技术[J].通信学报,2020,41(11):12-21.[2]㊀LIN Y,WANG M,ZHOU X,et al.Dynamic SpectrumInteraction of UAV Flight Formation Communication withPriority:A Deep Reinforcement Learning Approach [J].IEEE Transactions on Cognitive Communications and Net-working,2020,6(3):892-903.[3]㊀丁国如,孙佳琛,王海超,等.复杂电磁环境下频谱智能管控技术探讨[J].航空学报,2021,42(4):200-212.[4]㊀夏海洋,查淞,黄纪军,等.电磁频谱地图构建方法研究综述及展望[J].电波科学学报,2020,35(4):445-456.[5]㊀王圆春,肖东,林云.电磁频谱数据的关联规则挖掘[J /OL].电波科学学报:1-9[2022-11-29].http:ʊ /kcms/detail /41.1185.TN.20220601.1501.003.html.[6]㊀GUO L,WANG M,LIN Y.Electromagnetic EnvironmentPortrait Based on Big Data Mining[J].Wireless Commu-nications and Mobile Computing,2021(3):1-13.[7]㊀李伟,冯岩,熊能,等.基于无线电环境地图的频谱共享网络研究[J].电视技术,2016,40(10):60-66.[8]㊀ALFATTANI S,YONZACOGLU A.Indirect Methods forConstructing Radio Environment Map [C]ʊ2018IEEECanadian Conference on Electrical &Computer Engineer-ing (CCECE).Québec City:IEEE,2018:1-5.[9]㊀UMER M,KULIK L,TANIN E.Spatial Interpolation inWireless Sensor Networks:Localized Algorithms for Vario-gram Modeling and Kriging[J].Geoinformatica,2010,14(1):101-134.[10]AZPURUA M A,DOS RAMOS K.A Comparison of Spa-tial Interpolation Methods for Estimation of Average Elec-tromagnetic Field Magnitude[J].Progress in Electromag-netics Research M,2010,14:135-145.[11]胡炜林,刘辉,彭闯,等.基于Kriging 算法的电磁频谱地图构建技术研究[J].空军工程大学学报(自然科学版),2022,23(3):26-33.[12]李泓余,沈锋,韩路,等.一种模型和数据混合驱动的电磁频谱态势测绘方法[J].数据采集与处理,2022,37(2):321-335.[13]胡田钰,吴启晖,黄洋.基于生成对抗网络的三维频谱态势补全[J ].数据采集与处理,2021,36(6):1104-1116.[14]IMAI T,KITAO K,INOMATA M.Radio Propagation Pre-diction Model Using Convolutional Neural Networks byDeep Learning[C]ʊ201913th European Conference onAntennas and Propagation (EuCAP ).Yokosuka:IEEE,2019:1-5.[15]TEGANYA Y,ROMERO D.Deep Completion Autoencod-ers for Radio Map Estimation[J].IEEE Transactions on Wireless Communications,2021,21(3):1710-1724.[16]SAITO K,JIN Y,KANG C C,et al.Two-step Path LossPrediction by Artificial Neural Network for Wireless Serv-ice Area Planning [J].IEICE Communications Express,2019,8(12):611-616.[17]IIZUKA S,SIMO-SERRA E,ISHIKAWA H.Globally andLocally Consistent Image Completion[J].ACM Transac-tions on Graphics(ToG),2017,36(4):1-14.[18]LU K,BARNES N,ANWAR S,et al.Depth CompletionAuto-encoder[C]ʊ2022IEEE /CVF Winter Conference onApplications of Computer Vision Workshops (WACVW).Waikoloa:IEEE,2022:63-73.作者简介:㊀㊀张㊀晗㊀哈尔滨工程大学研究生㊂主要研究方向:电磁环境数据挖掘与可视化分析㊂㊀㊀韩㊀宇㊀博士,哈尔滨工程大学讲师㊂主要研究方向:复杂电磁环境认知㊁物联网海量信息接入㊂发表学术论文及专利10余篇,其中SCI 检索3篇,美国专利1篇;参与编写教材1部㊂作为项目主要负责人,承担国家自然科学基金项目1项㊂㊀㊀姜㊀航㊀博士,哈尔滨工程大学讲师㊂主要研究方向:毫米波通信㊁频谱认知㊁电磁目标识别㊂㊀㊀付江志㊀博士,哈尔滨工程大学讲师㊂主要研究方向:宽带数字通信㊁信号设计与处理㊁通信抗干扰㊂发表学术论文6篇,其中EI 检索4篇㊂作为主要成员,参与完成国家自然科学基金面上项目1项㊂㊀㊀(∗通信作者)林㊀云㊀哈尔滨工程大学教授,博士生导师,先进船舶通信与信息技术工业与信息化部重点实验室副主任㊂主要研究方向:智能无线电技术㊁人工智能和机器学习㊁大数据分析与挖掘㊁软件和认知无线电㊁信息安全与对抗㊁智能信息处理等㊂参与研发了具有自主知识产权的软件无线电通用开发平台,发表SCI 检索50余篇,ESI 高被引论文8篇,授权专利11项,荣获国防科技进步一等奖1项,中国电子学会科技进步一等奖1项,国防科技进步三等奖2项,黑龙江省科技进步三等奖1项㊂。
激光诱导击穿光谱技术及应用研究进展
第6卷 第4期2013年8月 中国光学 Chinese Optics Vol.6 No.4Aug.2013 收稿日期:2013⁃04⁃11;修订日期:2013⁃06⁃13 基金项目:国家自然科学基金面上项目(No.31270680,No.61076064);江苏省“六大高峰人才”资助项目(No.2011⁃XCL⁃018);江苏高校优势学科建设工程资助项目文章编号 1674⁃2915(2013)04⁃0490⁃11激光诱导击穿光谱技术及应用研究进展侯冠宇1,王 平1∗,佟存柱2(1.南京林业大学化学工程学院,江苏南京210037;2.中国科学院长春光学精密机械与物理研究所发光学及应用国家重点实验室,吉林长春130033)摘要:激光诱导击穿光谱(LIBS)技术是一种基于原子发射光谱学的元素定性、定量检测手段。
本文介绍了LIBS 技术的原理、应用方式、检测元素种类及检测极限;综述了该项技术在固体、液体、气体组分检测方面的技术发展,以及在环境检测、食品安全、生物医药、材料、军事、太空领域的应用进展。
最后,提出了高功率、高稳定的激光光源和准确的定量分析方法是LIBS 技术目前所面临的问题和挑战。
关 键 词:激光诱导击穿光谱;激光产生等离子体;元素分析;检测限中图分类号:O433.54;O657.319 文献标识码:A doi:10.3788/CO.20130604.0490Progress in laser⁃induced breakdown spectroscopyand its applicationsHOU Guan⁃yu 1,WANG Ping 1∗,TONG Cun⁃zhu 2(1.College of Chemical Engineering ,Nanjing Forestry University ,Nanjing 210037,China ;2.State Key Laboratory of Luminescence and Applications ,Changchun Institute of Optics ,Fine Mechanics and Physics ,Chinese Academy of Sciences ,Changchun 130033,China )∗Corresponding author ,E⁃mail :wp_lh@ Abstract :Laser⁃induced Breakdown Spectroscopy(LIBS)based on atomic emission spectral technology is a kind of convenient and sensitive approach for the qualitative and quantitative detection of elements.In this pa⁃per,the mechanism,detecting element types,detection limit and the recent progress of LIBS technology are reviewed.The progress of LIBS technology in component testing for solid,liquid and gas samples is expoundedin detail.The applications of LIBS in the environment test,food security,biological and medicines,material sciences,military and space fields are also presented.Finally,the challenges and problems for the LIBS tech⁃nology in high power and stable laser sources and accurately quantitative analysis method are discussed.Key words :laser⁃induced breakdown spectroscopy;laser⁃induced plasmon,element analysis;detection limit1 引 言 激光诱导击穿光谱(Laser⁃Induced Breakdown Spectroscopy,简称LIBS)技术是利用激光照射被测物体表面产生等离子体[1⁃2],通过检测等离子体光谱而获取物质成分和浓度的分析技术。
SignalShark实时频谱分析监测接收器RF方向找器与定位系统说明书
The new generation in signal analysisReal-Time Spectrum AnalyzerMonitoring ReceiverRF Direction Finding andLocalization SystemMore and more devices have to share the available frequency spectrum as aresult of new technologies such as the Internet of things (IoT), machine tomachine (M2M) or car to car (C2C) communications, and the rapidly growing4G/5G mobile networks.It doesn’t matter whether you are making a wideband measurement of entirefrequency ranges, or searching for hidden signals, or needing to reliablydetect very short impulses, or localizing interference signals –SignalSharkgives you all the measurement solutions you need to cope with the increasinglycomplex radio frequency spectrum. Its design and excellent performance makeit ideal for on-site measurements as well as for fully-fledged laboratory use. SignalShark. Seven senses for signalsSignalShark –there’s a reason for the name. Just like its namesake, theSignalShark is an extremely efficient hunter, perfectly designed for its task.Its prey: interference signals. Its success rate: Exceptional. The real-timeanalyzer is a successful hunter, thanks to the interplay of its highly developedseven sensory functions. Seven senses that don’t miss a thing, and that makeit easy for you to identify and track down interferers in real-time./watch?v=pSZdR27j5LQ&t=14s• Frequency range: 8 kHz to 8 GHz• Weight: Approx. 4.1 kg / 9 lbs (with one battery)• Dimensions: 230 × 335 × 85 mm (9.06ʺ× 13.19ʺ× 3.35ʺ)Make it your deviceSignalShark is ready for the future, thanks toits many expansion facilities, and it can beoptimally adapted as needed to the widestvariety of applications.SignalShark – the 40 MHz real-timespectrum analyzerWhether you are in the lab or out in thefield, you will have the right analysis toolin hand with the SignalShark. You will beconvinced by its truly outstanding RF perfor-mance, as well as by its easily understood,application-oriented operating concept.The high real-time bandwidth with very highFFT overlapping ensures that you can reliablycapture even extremely brief and infrequentevents. The unusually fast scan rate results invery short measurement times even if youneed to cover wider frequency bands thanthe real-time bandwidth. Comprehensiveevaluation tools make sure that you canperform current and future measurementand analysis tasks up to laboratory instru-ment standards reliably, simply, and faster.SignalShark – the monitoring receiverThe extremely High Dynamic Range (HDR) ofthe SignalShark ensures that you can reliablydetect even the weakest signals in the pre-sence of very strong signals, and not confusethem with the artifacts of a normal receiver.This is a basic requirement for most tasksin the field of radio monitoring. Alongsidethe real-time spectrum analyzer, there is areceiver for audio demodulation, level mea-surement, and modulation analysis, whichcan be tuned to any frequency and channelbandwidth within the 40 MHz real-timebandwidth. And, if you need even more thanthe analysis tools of the SignalShark, you canprocess the I/Q data from the receiver exter-nally as a real-time stream and store themon internal or external data storage media.SignalShark – the direction findingand localization systemIt is often necessary to locate the positionof a signal transmitter once the signals havebeen detected and analyzed. SignalSharksupports the new Automatic Direction-Finding Antennas (ADFA) from Narda,allowing you to localize the source veryquickly and reliably. In fact, localization ischild’s play, thanks to the integrated mapsand localization firmware. Conveniently,homing-in using an ADFA mounted on amoving vehicle is also supported. Powerful,state of the art algorithms minimize theeffects of false bearings caused by reflectionsoff urban surroundings in real-time. Extre-mely light weight and easy to use manualdirection finding antennas are availablefor ”last mile“ localization.V I D E OVideo display port for external monitor or projector USB 2.0 for keyboard, mouse, printer, etc.fast, convenient measurementBuilt-in loudspeaker gives clear,loud sound reproduction, even in noisy environments/watch?v=0jqrwU_jPcsV I D E OSignalShark is a handy, portable, battery powered measuring device, yet it boasts performance that is otherwise only found in large, heavy laboratory grade equipment. It can be readily used instead of such expensive equipment because of its wide range of connection facilities and measurement functions.SignalShark –the real-time spectrum analyzer• HDR: extremely low noise and distortion, simultaneously • real-time bandwidth: 40 MHz – FFT overlap: 75 % (Fspan > 20 MHz)– FFT overlap: 87.5 % (Fspan ≤20 MHz, RBW ≤400 kHz))– FFT size: up to 16,384• Minimum signal duration for 100 % POI: 3.125 µs at full amplitude accuracy • Minimum detectable signal duration: < 5 ns • Persistence: up to 1.6 million spectrums per second • Spectrogram time resolution: down to 31.25 µs • Spectrogram detectors: up to three at the same time • RBW: 1 Hz - 800 kHz in real-time spectrum mode, 1 Hz - 6.25 MHz in scan spectrum mode• Filters conforming to CISPR and MIL for EMC measurements • Scan speed: Scan rate up to 50 GHz/s • Detectors: +Pk, RMS, Avg, -Pk, Sample• Markers: 8, additional noise power density and channel power function •Peak table: shows up to 50 highest spectral peaksReliable detection of extremely short and rare events in a 40 MHz real-time bandwidthA real-time analyzer calculates the spectrum by applying the FFT on overlapping time segments of the underlying I/Q data within its real-time bandwidth. The real-time band-width is only one of the key parameters for a real-time analyzer. The probability of inter-cept, POI, is easily just as important. This parameter describes the minimum time that the signal must be present for it to be always detected without any reduction in level. This time is affected by the maximum resolution bandwidth RBW and the FFT overlap. The SignalShark is a match for established laboratory analyzers with its minimum duration of 3.125 µsec for 100 %POI and full amplitude accuracy. The mini-mum detectable signal duration is < 5 nsec.SignalShark accomplishes this by a large signal immunity in combination with a very low intrinsic noise as well as a high FFT overlap and its large resolution bandwidth.That is outstanding for a hand-held analyzer. To accomplish this, SignalShark generally operates with an 87.5 % overlap, which is again outstanding for a hand-held analyzer.This means that even the shortest impulses are detected and the full signal to noise ratio is maintained for longer signals.Spectrogram shows more details than everWith SignalShark, you can use up to three detectors at the same time for the Spectrogram view. This makes it possible for you to easily visualize impulse inter-ference on broadcast signals and get much more information from the spectrogram. The extraordinarily fine time resolution of 31.25 µs means that you can completely reveal the time signatures of many signals.With the I/Q Analyzer option, you can resolve the spectrogram even more, to less than 200 ns.Persistence ViewA color display of the spectrum shows how often the displayed levels have occurred. This enables you to detect signals that would be masked by stronger signals in a normal spectrum view.=SignalShark is not just a very powerful real-time spectrum analyzer. It is also the ideal monitoring receiver, thanks to its near ITU-ideal spectrum monitoring dynamic capabilities, second receiver path and demodulators.SignalShark –the monitoring receiver• HDR: extremely low noise and distortion, simultaneously • CBW: 25 Hz - 40 MHz (Parks-McClellan, α= 0.16)• Filters for EMC measurements: CISPR, MIL • Detectors: +Pk, RMS, Avg, -Pk, Sample• EMC detectors: CPk, CRMS, CAvg (compliant with CISPR)• Level units: dBm, dB µV, dB(µV/m) …• Level uncertainty: < ±2dB • AFC• Audio demodulators: CW, AM, Pulse, FM, PM, LSB, USB, ISB, I/Q • AGC & squelch for audio demodulators • Modulation measurements: AM, FM, PM • I/Q streaming: Vita 49 (sample rate ≤25,6 MHz)• Remote control protocol: SCPIThe benefit of HDRThe extremely high dynamic range (HDR) of the SignalShark ensures that you can reliably detect even the weakest signals in the presence of very strong signals. The SignalShark’s pre-selector allows it to suppress frequencies that would other-wise interfere with the measurement. The excellent dynamic range of the SignalShark is the result of the ideal combination of the displayed averaged noise level (DANL)with the so-called large-signal immunity parameters, i.e. the second and third order intermodulation intercept points (IP 2and IP 3).It is important that these three factors are always specified for the same device setting (e.g. no attenuation, no pre-amplifier), as they vary considerably according to the setting.DDC 2, the additional receiver pathThe tuning frequency and the channel band-width of an additional receiver path, DDC 2,can be set independently from the real-time spectrum analyzer path, DDC 1, within the real-time bandwidth of the SignalShark. The I/Q data can be streamed to external devices in real-time, or they can be processed by the SignalShark itself for level measurements,audio demodulation, and modulation measurements. The very steep cutoffchannel filters capture 100 % of the signal in the selected channel without any degra-dation while completely suppressing the adjacent channels.CISPR compliant EMC detectors now also available for on-site applications The facility for selecting all the filters and detectors necessary for CISPR or MIL com-pliant EMC measurements is also available for the receiver as well as for the spectrum. If an interferer is detected, you can now decide on the spot whether or not the device needs to be taken out of service because of violating EMC regulations.EQDDC 1Overlap BufferFFT DetectorsPersist.Persistence StreamSpectrum StreamADC DataDDC 2DetectorsDetectorsI/Q BufferTrigger UnitDemodulatorsAGCLevel StreamDem. Det.StreamDem. Audio StreamAM & FM StreamI/Q StreamI 2+Q2I 2+Q2PATH 1PATH 2The block circuit diagram shows the two, independent digital down converters (DDC). These make it possible e.g. to observe the spectrum of the signal spectrum and demodulate it at the same time independently within the real-time bandwidth.Automatic Direction Finding Antenna ADFA 1 + 2Narda offers a large number of automatic and directional antennas for the SignalShark. Their unique characteristics combined with the SignalShark makes them unbeatable.Automatic Direction Finding Antenna ADFA 1The frequency range of ADFA 1 makes it particularly suitable for localizing interferers,e.g. in mobile communications networks:Frequency range: 200 MHz - 2.7 GHz Nine dipoles arranged on a 380 mm diameter circle for DFA central monopole is used as a reference element for DF or as an omnidirectional monitoring antennaBuilt-in phase shifter and switch matrix Direction finding method: correlative interferometerBearing uncertainty: 1° RMS (typ.)Built-in electronic compassBuilt-in GNSS receiver with antenna and PPS outputDiameter: 480 mmAutomatic Direction Finding Antenna ADFA 2 (available 2019)This ADFA is suitable for a wide range of localization tasks due to its wide frequency range:Frequency range: (500 kHz) 10 MHz -8 GHz Two crossed coils for DF at low frequencies Nine dipoles arranged on a 380 mm dia-meter circle for DF at medium frequencies Nine monopoles arranged on a 125 mm diameter circle for DF at high frequencies A central monopole is used as a reference element for DF or as an omnidirectional monitoring antennaBuilt-in phase shifter and switch matrix Direction finding method: Watson-Watt or correlative interferometerBearing uncertainty (10 MHz - 200 MHz): 2° RMS (typ.)Bearing uncertainty (200 MHz - 8 GHz): 1° RMS (typ.)Built-in electronic compassBuilt-in GNSS receiver with antenna and PPS output Diameter: 480 mm Automatic Direction Finding Antenna ADFA accessoriesConnecting cable, length 5 m or 15 m,low lossTripod including mounting accessories Mounting kit for magnetic attachment to a vehicle roofMounting kit for mast attachmentAfter you have localized the signal by SignalShark and ADFA using the car, you will need for last mile or to enter a building Narda’s handy, feather-light directional antennas and active antenna handle. They are the ideal choice in this situation. The antenna handle does more than just hold the antenna. Among other features, it has a built-in operating button that allows you to perform the main steps during manual direction finding, making the combination unbeatable.and take bearings on very weak or distant signals. The preamplifier gain is taken into account automatically when you make field strength or level measurements.The integrated operating button lets you make the main steps in the manual direction finding process.The following antennas to fit the antenna handle are available:• Loop Antenna: 9 kHz - 30 MHz• Directional Antenna 1: 20 MHz - 250 MHz • Directional Antenna 2: 200 MHz - 500 MHz • Directional Antenna 3: 400 MHz - 8 GHz A plug-in adapter with male N connector allows you to take advantage of the features of the handle even when you are using third-party antennas or external filters.Directional antenna 3400 MHz - 8 GHz350 g / 0.77 lbsDirectional antenna 1 20 MHz - 250 MHz 400 g / 0.88 lbs Loop antenna 9 kHz - 30 MHz 380 g / 0.84 lbs Directional antenna 2 200 MHz - 500 MHz 300 g / 0.66 lbs Active antenna handle with integrated compass and preamplifier 9 kHz - 8 GHz 470 g / 1.04 lbsAdapter,male N connectorN Antenna Elements0°90°180°270°Element SwitchReference Elementn1Quadrature Phase Shifter(Smart Antenna)+The Narda antenna handle and directional antennas are extremely light, making for fatigue-free signal searches.The convenient plug-in system allows you to change antennas very quickly.SignalShark recognizes the antenna and applies the appropriate antenna factors for field strength measurements automatically.SignalShark receives the azimuth,elevation and polarization of the antenna from the 3D electronic compass built into the handle, so manual direction finding could hardly be simpler.The preamplifier built into the handle is activated and deactivated bySignalShark, so you can further reduce SignalShark’s low noise figure to detectYou will often need to locate the position of a signal transmitter once thesignals have been detected or analyzed. SignalShark combined with Narda’snew automatic direction finding antennas (ADFA) and the very powerfulmap and localization firmware provides reliable bearings in the twinklingof an eye. The bearing results are processed by the SignalShark withoutneeding an external PC. Reliable localization of transmitters has not beenpossible before with so few hardware components.Transmitter localizationSignalShark simplifies transmitter localizationby autonomously evaluating all the availablebearing results and plotting them on a map,using a statistical distribution of bearinglines. The result is a so-called “heat map”,on which the possible location of the trans-mitter is plotted and color-coded accordingto probability. SignalShark also draws anellipse on the map centered on the estima-ted position of the transmitter and indicatingthe area where the transmitter has a 95 %probability of being located. The algorithmused by SignalShark to calculate the positionof an emitter is extremely powerful. It candetermine the position of the emitter bycontinuous direction finding when movingaround in a vehicle, even in a complexenvironment such as an inner-city area.The calculation is continuous inreal-time, so you can viewthe changing heat mapon the screen of theSignalShark andFast automatic direction findingSignalShark supports the new automaticdirection finding antennas (ADFA) fromNarda, which let you take a completebearing cycle in as little as 1.2 ms.The omnidirectional channel power and thespectrum are also measured during a bearingcycle, so you can monitor changes in thesignal level or spectrum concurrently withthe bearings. The AFDAs use differentantenna arrays, depending on the frequencyrange. At low frequencies, a pair of crossedcoils are used for the Watson-Watt methodof direction finding. At medium and highfrequencies, a circular array of nine dipolesor monopoles is used for the correlativeinterferometer direction finding method.SignalShark –The RF direction finding and localization system• Frequency range ADFA 1: 200 MHz - 2.7 GHz• Frequency range ADFA 2: 10 MHz - 8 GHz• Azimuth and elevation bearings• DF quality index• Complete bearing cycle: down to 1.2 ms• Omnidirectional level and spectrum during DF process• Uses OpenStreetMaps, other map formats can be imported• Easy to use, powerful map and localization software• The map and localization software runs on the handheldunit itselfThe SignalShark is a very powerful platform that Narda is continuously expanding. Options that will be available for delivery in 2019 are described below. Only the firmware of the SignalShark will be used to realize these options, which will be capable of on-site activation.High time resolution spectrogram HTRSalso available in the spectrum pathIn real-time spectrum mode, the ring buffer ofthe SignalShark records the I/Q data from thereal-time spectrum path rather than from thereceiver I/Q data. If you or a trigger eventhalts the real-time analyzer, the last up to200 million I/Q samples of the monitoredfrequency range are available. This correspondsto a timespan of at least 4 s, so you can zoomin on the spectrogram with a resolution ofbetter than 200 ns when the analyzer is halted.The FFT overlap can be up to 93.75 %, and nodetectors are needed that could reduce thetime resolution. You can even subsequentlyalter the RBW. The persistence view also adjustsso that it exactly summarizes the spectrumsin the time period covered by the zoomedsegment. This ensures that all the time orspectral details in the I/Q data can be madevisible. You can of course also save the I/Qdata of the zoomed segment.DF SpectrumThe SignalShark can find the directions ofseveral transmitters simultaneously in DFspectrum evaluation mode. This mode offersa persistence spectrum and a spectrogramof the azimuth in addition to the usual levelspectrum and spectrogram view. You canalso monitor frequency ranges that arewider than the real-time bandwidth of theSignalShark. You can distinguish betweendifferent transmitters much more easilythan before by means of DF spectrum mode,because the SignalShark shows you thedirection of incidence as well as the levelof each frequency bin.SignalShark I/Q analyzerSignalShark has a ring buffer for up to 200 million I/Q samples. The receiver I/Q data are normally written continuouslyto the ring buffer. The recording can be stopped by a trigger event. The recorded I/Q data are then transferred to the CPU of the SignalShark, where they are further processed.The following trigger sources are available: Frequency mask triggerReceiver levelExternal trigger sourceTimestampUser inputFree runThe following I/Q data views are available: I and Q versus timeMagnitude versus time (Zero-span) Vector diagramHigh time resolution spectrogram Persistence You can of course also save the I/Q data as adata set, and you can even stream the datadirectly to permanent storage media in orderto make very long recordings of the I/Q data.You can then replay such long-term recor-dings using the integrated I/Q analyzer, orprocess them externally.2 x 10 MHz LTE signal recorded in a HTRS. Time resolution1 µs. The extremely high time resolution renders the signaltransparent at low traffic levels (right), so you can spotpossible interference within the frame structure.More Information about technical details andaccessories like transport case and car chargerunit can be found in the SignalShark data sheet./en/signalsharkNarda is a leading supplier …N S T S 06/18 E 0333A T e c h n i c a l a d v an c e s , e r r o r s a n d o m i s s i o n s e x c l u d e d .© N a r d a S a f e t y T e s t S o l u t i o n s 2014. ® T h e n a m e a n d l o g o a r e t h e r e g i s t e r e d t r a d e m a r k s o f N a r d a S a f e t y T e s t S o l u t i o n s G m b H a n d L 3 C o m m u n i c a t i o n s H o l d i n g s , I n c .—T r a d e n a m e s a r e t h e t r a d e m a r k s o f t h e i r o w n e r s .r o e n e r -d e s i g n .d eNarda Safety Test Solutions 435 Moreland RoadHauppauge, NY11788, USA Phone +1 631 231-1700Fax +1 631 231-1711**************************… of measuring equipment in the RF test and measurement, EMF safety and EMC sectors. The RF test and measurement sector covers analyzers and instruments for measuring andidentifying radio sources. The EMF safety product spectrum includes wideband and frequency-selective measuring devices, and monitors for wide area coverage or which can be worn on the body for personal safety. The EMC sector offers instruments for determining the electro-magnetic compatibility of devices under the PMM brand. The range of services includes servicing, calibration, accredited calibration, and continuous training programs.Narda Safety Test Solutions GmbH Sandwiesenstraße 772793 Pfullingen, Germany Tel. +49 7121 97 32 0Fax +49 7121 97 32 790********************* /en/signalshark。
药物分析专业英语
(dissolution) vessel 溶出杯(FTIR) 傅里叶变换红外光谱仪13C-NMR spectrum,13CNMR 碳-13核磁共振谱1ength basis 长度基准1H-NMR 氢谱2D-NMR 二维核磁共振谱：2D-NMR3D-spectrochromatogram 三维光谱－波谱图Aa stream of nitrogen 氮气流a wide temperature range 宽的温度范围absolute detector response 检测器绝对响应(值)absolute entropy 绝对熵absolute error 绝对误差absolute reaction rate theory 绝对反应速率理论absolute temperature scale 绝对温标absorbance 吸光度，而不是吸收率（absorptance）。
当我们忽略反射光强时，透射率（T）与吸光度（A）满足如下关系式：A=lg(1/T)。
absorbance noise, absorbing noise 吸光度噪音。
也称光谱的稳定性，是指在确定的波长范围内对样品进行多次扫描，得到光谱的均方差。
吸光度噪音是体现仪器稳定性的重要指标。
将样品信号强度与吸光度噪音相比可计算出信噪比。
absorbed water 吸附水absorptance 吸收率absorptant 吸收剂absorption band 吸收带absorption cell 吸收池absorption curve 吸收光谱曲线/光吸收曲线absorption tube 吸收管abundance 丰度。
即具有某质荷比离子的数量accelerated solvent extraction(ASE) 加速溶剂萃取accelerated testing 加速试验accelerating decomposition 加速破坏acceptance limit，acceptance criterion 验收限度，合格标准accidental error 随机误差accuracy 准确度。
紫外可见吸收光谱 微反应器
紫外可见吸收光谱微反应器英文回答：Ultraviolet-visible (UV-Vis) absorption spectroscopy is a commonly used technique in analytical chemistry to determine the presence and concentration of various compounds in a sample. This spectroscopic method involves the measurement of the absorption of light in the UV-Vis range (typically 190-900 nm) by a sample. The absorption spectrum obtained provides valuable information about the electronic transitions occurring in the molecules presentin the sample.UV-Vis absorption spectroscopy relies on the fact that molecules absorb light in the UV-Vis region when their electrons undergo transitions from lower energy levels to higher energy levels. The absorption of light causes the electrons to move from the ground state to an excited state. The energy difference between these two states correspondsto a specific wavelength of light, which can be detectedand measured using a spectrophotometer.The absorption spectrum obtained from UV-Vis spectroscopy consists of a series of peaks and valleys, each corresponding to a specific electronic transition. The position and intensity of these peaks provide information about the nature and concentration of the compounds present in the sample. For example, a compound with a strong absorption peak at a certain wavelength indicates the presence of chromophores that absorb light at that specific wavelength.UV-Vis absorption spectroscopy has a wide range of applications in various fields, including pharmaceuticals, environmental analysis, and biochemistry. It is commonly used in the quantification of analytes in solution, such as determining the concentration of a drug in a pharmaceutical formulation or the amount of a pollutant in an environmental sample. UV-Vis spectroscopy is also used to study the kinetics of chemical reactions, as the absorption of light can be directly related to the concentration of reactants or products.In recent years, there has been an increasing interest in the development of microreactors for performing chemical reactions. Microreactors, also known as microfluidic devices, are miniaturized reaction systems that enable the efficient and controlled synthesis of various compounds. These devices offer advantages such as improved heat and mass transfer, enhanced reaction selectivity, and reduced reaction times.Microreactors can be integrated with UV-Vis spectroscopy to monitor and analyze chemical reactions in real-time. By coupling a microreactor with a spectrophotometer, it is possible to continuously measure the absorption spectrum of the reaction mixture as the reaction progresses. This provides valuable information about the reaction kinetics, intermediate species, and reaction pathways.For example, consider a reaction where a starting material undergoes a series of transformations to form a final product. By monitoring the UV-Vis absorption spectrumof the reaction mixture at different time points, one can observe the disappearance of the starting material's absorption peak and the appearance of new peaks corresponding to intermediate species and the final product. This allows for the determination of reaction rates,reaction mechanisms, and the identification of reaction intermediates.In conclusion, UV-Vis absorption spectroscopy is a powerful analytical technique that provides valuable information about the electronic transitions occurring in molecules. It is widely used in various fields for the quantification of analytes and the study of chemical reactions. When coupled with microreactors, UV-Vis spectroscopy allows for real-time monitoring and analysisof chemical reactions, providing insights into reaction kinetics and mechanisms.中文回答：紫外可见（UV-Vis）吸收光谱是在分析化学中常用的一种技术，用于确定样品中各种化合物的存在和浓度。
NDT常用中英文对照表
该表节选自《中英文无损检测名词术语查询系统（NDTGP）》English ChineseA.C magnetic saturation 交流磁饱和Absorbed dose 吸收剂量Absorbed dose rate 吸收剂量率Acceptance limits 验收范围Acceptance level 验收水平Acceptance standard 验收标准Accumulation test 累积检测Acoustic emission count（emission count）声发射计数（发射计数）Acoustic emission transducer 声发射换能器（声发射传感器）Acoustic emission(AE) 声发射Acoustic holography 声全息术Acoustic impedance 声阻抗Acoustic impedance matching 声阻抗匹配Acoustic impedance method 声阻法Acoustic wave 声波Acoustical lens 声透镜Acoustic—ultrasonic 声-超声（AU）Activation 活化Activity 活度Adequate shielding 安全屏蔽Ampere turns 安匝数Amplitude 幅度Angle beam method 斜射法Angle of incidence 入射角Angle of reflection 反射角Angle of spread 指向角Angle of squint 偏向角Angle probe 斜探头Angstrom unit 埃(A)Area amplitude response curve 面积幅度曲线Area of interest 评定区Artificial discontinuity 人工不连续性Artifact 假缺陷Artificial defect 人工缺陷Artificial discontinuity 标准人工缺陷A-scan A型扫描A-scope; A-scan A型显示Attenuation coefficient 衰减系数Attenuator 衰减器Audible leak indicator 音响泄漏指示器Automatic testing 自动检测Autoradiography 自射线照片Evaluation 评定Barium concrete 钡混凝土Barn 靶Base fog 片基灰雾Bath 槽液Bayard- Alpert ionization gage B- A型电离计Beam 声束Beam ratio 光束比Beam angle 束张角Beam axis 声束轴线Beam index 声束入射点Beam path location 声程定位Beam path; path length 声程Beam spread 声束扩散Betatron 电子感应加速器Bimetallic strip gage 双金属片计Bipolar field 双极磁场Black light filter 黑光滤波器Black light; ultraviolet radiation 黑光Blackbody 黑体Blackbody equivalent temperature 黑体等效温度Bleakney mass spectrometer 波利克尼质谱仪Bleed out 渗出Bottom echo 底面回波Bottom surface 底面Boundary echo(first) 边界一次回波Bremsstrahlung 轫致辐射Broad-beam condition 宽射束Brush application 刷涂B-scan presentation B型扫描显示B-scope; B-scan B型显示C- scan C型扫描Calibration ,instrument 设备校准Capillary action 毛细管作用Carrier fluid 载液Carry over of penetrant 渗透剂移转Cassette 暗合Cathode 阴极Central conductor 中心导体Central conductor method 中心导体法Characteristic curve 特性曲线Characteristic curve of film 胶片特性曲线Characteristic radiation 特征辐射Chemical fog 化学灰雾Cine-radiography 射线(活动)电影摄影术Contact pads 接触垫Circumferential coils 圆环线圈Circumferential field 周向磁场Circumferential magnetization method 周向磁化法Clean 清理Clean- up 清除Clearing time 定透时间Coercive force 矫顽力Coherence 相干性Coherence length 相干长度（谐波列长度）Coi1，test 测试线圈Coil size 线圈大小Coil spacing 线圈间距Coil technique 线圈技术Coil method 线圈法Coil reference 线圈参考Coincidence discrimination 符合鉴别Cold-cathode ionization gage 冷阴极电离计Collimator 准直器Collimation 准直Collimator 准直器Combined color contrast and fluorescent penetrant 着色荧光渗透剂Compressed air drying 压缩空气干燥Compressional wave 压缩波Compton scatter 康普顿散射Continuous emission 连续发射Continuous linear array 连续线阵Continuous method 连续法Continuous spectrum 连续谱Continuous wave 连续波Contract stretch 对比度宽限Contrast 对比度Contrast agent 对比剂Contrast aid 反差剂Contrast sensitivity 对比灵敏度Control echo 监视回波Control echo 参考回波Couplant 耦合剂Coupling 耦合Coupling losses 耦合损失Cracking 裂解Creeping wave 爬波Critical angle 临界角Cross section 横截面Cross talk 串音Cross-drilled hole 横孔Crystal 晶片C-scope; C-scan C型显示Curie point 居里点Curie temperature 居里温度Curie(Ci) 居里Current flow method 通电法Current induction method 电流感应法Current magnetization method 电流磁化法Cut－off level 截止电平Dead zone 盲区Decay curve 衰变曲线Decibel(dB) 分贝Defect 缺陷Defect resolution 缺陷分辨力Defect detection sensitivity 缺陷检出灵敏度Defect resolution 缺陷分辨力Definition 清晰度Definition，image definition 清晰度，图像清晰度Demagnetization 退磁Demagnetization factor 退磁因子Demagnetizer 退磁装置Densitometer 黑度计Density 黑度（底片）Density comparison strip 黑度比较片Detecting medium 检验介质Detergent remover 洗净液Developer 显像剂Developer station 显像工位Developer，agueons 水性显象剂Developer，dry 干显象剂Developer，liquid film 液膜显象剂Developer，nonaqueous （sus- pendible）非水（可悬浮）显象剂Developing time 显像时间Development 显影Diffraction mottle 衍射斑Diffuse indications 松散指示Diffusion 扩散Digital image acquisition system 数字图像识别系统Dilatational wave 膨胀波Dip and drain station 浸渍和流滴工位Direct contact magnetization 直接接触磁化Direct exposure imaging 直接曝光成像Direct contact method 直接接触法Directivity 指向性Discontinuity 不连续性Distance- gain- size-German A VG 距离- 增益- 尺寸（DGS德文为A VG）Distance marker; time marker 距离刻度Dose equivalent 剂量当量Dose rate meter 剂量率计Dosemeter 剂量计Double crystal probe 双晶片探头Double probe technique 双探头法Double transceiver technique 双发双收法Double traverse technique 二次波法Drag out 带出Drain time 滴落时间Drain time 流滴时间Drift 漂移Dry method 干法Dry powder 干粉Dry technique 干粉技术Dry developer 干显像剂Dry developing cabinet 干显像柜Dry method 干粉法Drying oven 干燥箱Drying station 干燥工位Drying time 干燥时间D-scope; D-scan D型显示Dual search unit 双探头Dual-focus tube 双焦点管Duplex-wire image quality indicator 双线像质指示器Duration 持续时间Dwell time 停留时间Dye penetrant 着色渗透剂Dynamic leak test 动态泄漏检测Dynamic leakage measurement 动态泄漏测量Dynamic range 动态范围Dynamic radiography 动态射线透照术Echo 回波Echo frequency 回波频率Echo height 回波高度Echo indication 回波指示Echo transmittance of sound pressure 往复透过率Echo width 回波宽度Eddy current 涡流Eddy current flaw detector 涡流探伤仪Eddy current testing 涡流检测Edge 端面Edge effect 边缘效应Edge echo 棱边回波Edge effect 边缘效应Effective depth penetration （EDP）有效穿透深度Effective focus size 有效焦点尺寸Effective magnetic permeability 有效磁导率Effective permeability 有效磁导率Effective reflection surface of flaw 缺陷有效反射面Effective resistance 有效电阻Elastic medium 弹性介质Electric displacement 电位移Electrical center 电中心Electrode 电极Electromagnet 电磁铁Electro-magnetic acoustic transducer 电磁声换能器Electromagnetic induction 电磁感应Electromagnetic radiation 电磁辐射Electromagnetic testing 电磁检测Electro-mechanical coupling factor 机电耦合系数Electron radiography 电子辐射照相术Electron volt 电子伏恃Electronic noise 电子噪声Electrostatic spraying 静电喷涂Emulsification 乳化Emulsification time 乳化时间Emulsifier 乳化剂Encircling coils 环绕式线圈End effect 端部效应Energizing cycle 激励周期Equalizing filter 均衡滤波器Equivalent 当量Equivalent I．Q. I. Sensitivity 象质指示器当量灵敏度Equivalent nitrogen pressure 等效氮压Equivalent penetrameter sensitivity 透度计当量灵敏度Equivalent method 当量法Erasabl optical medium 可探光学介质Etching 浸蚀Evaluation 评定Evaluation threshold 评价阈值Event count 事件计数Event count rate 事件计数率Examination area 检测范围Examination region 检验区域Exhaust pressure/discharge pressure 排气压力Exhaust tubulation 排气管道Expanded time-base sweep 时基线展宽Exposure 曝光Exposure table 曝光表格Exposure chart 曝光曲线Exposure fog 曝光灰雾Exposure，radiographic exposure 曝光，射线照相曝光Extended source 扩展源Facility scattered neutrons 条件散射中子False indication 假指示Family 族Far field 远场Feed-through coil 穿过式线圈Field，resultant magnetic 复合磁场Fill factor 填充系数Film speed 胶片速度Film badge 胶片襟章剂量计Film base 片基Film contrast 胶片对比度Film gamma 胶片γ值Film processing 胶片冲洗加工Film speed 胶片感光度Film unsharpness 胶片不清晰度Film viewing screen 观察屏Filter 滤波器/滤光板Final test 复探Flat-bottomed hole 平底孔Flat-bottomed hole equivalent 平底孔当量Flaw 伤Flaw characterization 伤特性Flaw echo 缺陷回波Flexural wave 弯曲波Floating threshold 浮动阀值Fluorescence 荧光Fluorescent examination method 荧光检验法Fluorescent magnetic particle inspection 荧光磁粉检验Fluorescent dry deposit penetrant 干沉积荧光渗透剂Fluorescent light 荧光Fluorescent magnetic powder 荧光磁粉Fluorescent penetrant 荧光渗透剂Fluorescent screen 荧光屏Fluoroscopy 荧光检查法Flux leakage field 磁通泄漏场Flux lines 磁通线Focal spot 焦点Focal distance 焦距Focus length 焦点长度Focus size 焦点尺寸Focus width 焦点宽度Focus(electron) 电子焦点Focused beam 聚焦声束Focusing probe 聚焦探头Focus-to-film distance(f.f.d) 焦点-胶片距离（焦距）Fog 底片灰雾Fog density 灰雾密度Foot candle 英尺烛光Frequency 频率Frequency constant 频率常数Fringe 干涉带Front distance 前沿距离Front distance of flaw 缺陷前沿距离Full- wave direct current（FWDC）全波直流Fundamental frequency 基频Furring 毛状迹痕Gage pressure 表压Gain 增益Gamma radiography γ射线透照术Gamma ray source γ射线源Gamma ray sourc e container γ射线源容器Gamma rays γ射线Gamma-ray radiographic equipment γ射线透照装置Gap scanning 间隙扫查Gas 气体Gate 闸门Gating technique 选通技术Gauss 高斯Geiger-Muller counter 盖革.弥勒计数器Geometric unsharpness 几何不清晰度Gray(Gy) 戈瑞Grazing incidence 掠入射Grazing angle 掠射角Group velocity 群速度Half life 半衰期Half- wave current （HW）半波电流Half-value layer(HVL) 半值层Half-value method 半波高度法Halogen 卤素Halogen leak detector 卤素检漏仪Hard X-rays 硬X射线Hard-faced probe 硬膜探头Harmonic analysis 谐波分析Harmonic distortion 谐波畸变Harmonics 谐频Head wave 头波Helium bombing 氦轰击法Helium drift 氦漂移Helium leak detector 氦检漏仪Hermetically tight seal 气密密封High vacuum 高真空High energy X-rays 高能X射线Holography (optical) 光全息照相Holography，acoustic 声全息Hydrophilic emulsifier 亲水性乳化剂Hydrophilic remover 亲水性洗净剂Hydrostatic text 流体静力检测Hysteresis 磁滞Hysteresis 磁滞IACS IACSID coil ID线圈Image definition 图像清晰度Image contrast 图像对比度Image enhancement 图像增强Image magnification 图像放大Image quality 图像质量Image quality indicator sensitivity 像质指示器灵敏度Image quality indicator(IQI)/image quality indication 像质指示器Imaging line scanner 图像线扫描器Immersion probe 液浸探头Immersion rinse 浸没清洗Immersion testing 液浸法Immersion time 浸没时间Impedance 阻抗Impedance plane diagram 阻抗平面图Imperfection 不完整性Impulse eddy current testing 脉冲涡流检测Incremental permeability 增量磁导率Indicated defect area 缺陷指示面积Indicated defect length 缺陷指示长度Indication 指示Indirect exposure 间接曝光Indirect magnetization 间接磁化Indirect magnetization method 间接磁化法Indirect scan 间接扫查Induced field 感应磁场Induced current method 感应电流法Infrared imaging system 红外成象系统Infrared sensing device 红外扫描器Inherent fluorescence 固有荧光Inherent filtration 固有滤波Initial permeability 起始磁导率Initial pulse 始脉冲Initial pulse width 始波宽度Inserted coil 插入式线圈Inside coil 内部线圈Inside- out testing 外泄检测Inspection 检查Inspection medium 检查介质Inspection frequency/ test frequency 检测频率Intensifying factor 增感系数Intensifying screen 增感屏Interal,arrival time （Δtij)/arrival time interval（Δtij）到达时间差(Δtij) Interface boundary 界面Interface echo 界面回波Interface trigger 界面触发Interference 干涉Interpretation 解释Ion pump 离子泵Ion source 离子源Ionization chamber 电离室Ionization potential 电离电位Ionization vacuum gage 电离真空计Ionography 电离射线透照术Irradiance，E 辐射通量密度，EIsolation 隔离检测Isotope 同位素K value K值Kaiser effect 凯塞(Kaiser)效应Kilo volt kv 千伏特Kiloelectron volt keV千电子伏特Krypton 85 氪85L／D ratio L/D比Lamb wave 兰姆波Latent image 潜象Lateral scan 左右扫查Lateral scan with oblique angle 斜平行扫查Latitude (of an emulsion) 胶片宽容度Lead screen 铅屏Leak 泄漏孔Leak artifact 泄漏器Leak detector 检漏仪Leak testing 泄漏检测Leakage field 泄漏磁场Leakage rate 泄漏率Leechs 磁吸盘Lift-off effect 提离效应Light intensity 光强度Limiting resolution 极限分辨率Line scanner 线扫描器Line focus 线焦点Line pair pattern 线对检测图Line pairs per millimetre 每毫米线对数Linear (electron) accelerator(LINAC) 电子直线加速器Linear attenuation coefficient 线衰减系数Linear scan 线扫查Linearity （time or distance）线性（时间或距离）Linearity，amplitude 幅度线性Lines of force 磁力线Lipophilic emulsifier 亲油性乳化剂Lipophilic remover 亲油性洗净剂Liquid penetrant examination 液体渗透检验Liquid film developer 液膜显像剂Local magnetization 局部磁化Local magnetization method 局部磁化法Local scan 局部扫查Localizing cone 定域喇叭筒Location 定位Location accuracy 定位精度Location computed 定位，计算Location marker 定位标记Location upon delta-T 时差定位Location，clusfer 定位，群集Location，continuous AE signal 定位，连续AE信号Longitudinal field 纵向磁场Longitudinal magnetization method 纵向磁化法Longitudinal resolution 纵向分辨率Longitudinal wave 纵波Longitudinal wave probe 纵波探头Longitudinal wave technique 纵波法Loss of back reflection 背面反射损失Loss of back reflection 底面反射损失Love wave 乐甫波Low energy gamma radiation 低能γ辐射Low－energy photon radiation 低能光子辐射Luminance 亮度Luminosity 流明Lusec 流西克Maga or million electron volts MeV兆电子伏特Magnetic history 磁化史Magnetic hysteresis 磁性滞后Magnetic particle field indication 磁粉磁场指示器Magnetic particle inspection flaw indications 磁粉检验的伤显示Magnetic circuit 磁路Magnetic domain 磁畴Magnetic field distribution 磁场分布Magnetic field indicator 磁场指示器Magnetic field meter 磁场计Magnetic field strength 磁场强度(H)Magnetic field/field，magnetic 磁场Magnetic flux 磁通Magnetic flux density 磁通密度Magnetic force 磁化力Magnetic leakage field 漏磁场Magnetic leakage flux 漏磁通Magnetic moment 磁矩Magnetic particle 磁粉Magnetic particle indication 磁痕Magnetic particle testing/magnetic particle examination 磁粉检测Magnetic permeability 磁导率Magnetic permeability 磁导率Magnetic pole 磁极Magnetic saturataion 磁饱和Magnetic saturation 磁饱和Magnetic slorage meclium 磁储介质Magnetic writing 磁写Magnetizing 磁化Magnetizing current 磁化电流Magnetizing coil 磁化线圈Magnetostrictive effect 磁致伸缩效应Magnetostrictive transducer 磁致伸缩换能器Main beam 主声束Manual testing 手动检测Markers 时标MA-scope; MA-scan MA型显示Masking 遮蔽Mass attcnuation coefficient 质量吸收系数Mass number 质量数Mass spectrometer （M.S.）质谱仪Mass spectrometer leak detector 质谱检漏仪Mass spectrum 质谱Master/slave discrimination 主从鉴别MDTD 最小可测温度差Mean free path 平均自由程Medium vacuum 中真空Mega or million volt MV兆伏特Micro focus X - ray tube 微焦点X 光管Microfocus radiography 微焦点射线透照术Micrometre 微米Micron of mercury 微米汞柱Microtron 电子回旋加速器Milliampere 毫安（mA）Millimetre of mercury 毫米汞柱Minifocus x- ray tube 小焦点调射线管Minimum detectable leakage rate 最小可探泄漏率Minimum resolvable temperature difference （MRTD）最小可分辨温度差（MRDT）Mode 波型Mode conversion 波型转换Mode transformation 波型转换Moderator 慢化器Modulation transfer function （MTF）调制转换功能（MTF）Modulation analysis 调制分析Molecular flow 分子流Molecular leak 分子泄漏Monitor 监控器Monochromatic 单色波Movement unsharpness 移动不清晰度Moving beam radiography 可动射束射线透照术Multiaspect magnetization method 多向磁化法Multidirectional magnetization 多向磁化Multifrequency eddy current testing 多频涡流检测Multiple back reflections 多次背面反射Multiple reflections 多次反射Multiple back reflections 多次底面反射Multiple echo method 多次反射法Multiple probe technique 多探头法Multiple triangular array 多三角形阵列Narrow beam condition 窄射束NC NCNear field 近场Near field length 近场长度Near surface defect 近表面缺陷Net density 净黑度Net density 净(光学)密度Neutron 中子Neutron radiography 中子射线透照Neutron radiography 中子射线透照术Newton （N）牛顿Nier mass spectrometer 尼尔质谱仪Noise 噪声Noise 噪声Noise equivalent temperature difference （NETD）噪声当量温度差（NETD）Nominal angle 标称角度Nominal frequency 标称频率Non-aqueous liquid developer 非水性液体显像剂Noncondensable gas 非冷凝气体Nondcstructivc Examination（NDE）无损试验Nondestructive Evaluation（NDE）无损评价Nondestructive Inspection（NDI）无损检验Nondestructive Testing（NDT）无损检测Nonerasble optical data 可固定光学数据Nonferromugnetic material 非铁磁性材料Nonrelevant indication 非相关指示Non-screen-type film 非增感型胶片Normal incidence 垂直入射（亦见直射声束）Normal permeability 标准磁导率Normal beam method; straight beam method 垂直法Normal probe 直探头Normalized reactance 归一化电抗Normalized resistance 归一化电阻Nuclear activity 核活性Nuclide 核素Object plane resolution 物体平面分辨率Object scattered neutrons 物体散射中子Object beam 物体光束Object beam angle 物体光束角Object-film distance 被检体-胶片距离Object一film distance 物体- 胶片距离Over development 显影过度Over emulsfication 过乳化Overall magnetization 整体磁化Overload recovery time 过载恢复时间Over washing 过洗Oxidation fog 氧化灰雾P PPair production 偶生成Pair production 电子对产生Pair production 电子偶的产生Palladium barrier leak detector 钯屏检漏仪Panoramic exposure 全景曝光Parallel scan 平行扫查Paramagnetic material 顺磁性材料Parasitic echo 干扰回波Partial pressure 分压Particle content 磁悬液浓度Particle velocity 质点(振动)速度Pascal （Pa）帕斯卡（帕）Pascal cubic metres per second 帕立方米每秒（Pa•m3/s ）Path length 光程长Path length difference 光程长度差Pattern 探伤图形Peak current 峰值电流Penetrameter 透度计Penetrameter sensitivity 透度计灵敏度Penetrant 渗透剂Penetrant comparator 渗透对比试块Penetrant flaw detection 渗透探伤Penetrant removal 渗透剂去除Penetrant station 渗透工位Penetrant，water- washable 水洗型渗透剂Penetration 穿透深度Penetration time 渗透时间Permanent magnet 永久磁铁Permeability coefficient 透气系数Permeability，a-c 交流磁导率Permeability，d－c 直流磁导率Phantom echo 幻象回波Phase analysis 相位分析Phase angle 相位角Phase controlled circuit breaker 断电相位控制器Phase detection 相位检测Phase hologram 相位全息Phase sensitive detector 相敏检波器Phase shift 相位移Phase velocity 相速度Phase-sensitive system 相敏系统Phillips ionization gage 菲利浦电离计Phosphor 荧光物质Photo fluorography 荧光照相术Photoelectric absorption 光电吸收Photographic emulsion 照相乳剂Photographic fog 照相灰雾Photostimulable luminescence 光敏发光Piezoelectric effect 压电效应Piezoelectric material 压电材料Piezoelectric stiffness constant 压电劲度常数Piezoelectric stress constant 压电应力常数Piezoelectric transducer 压电换能器Piezoelectric voltage constant 压电电压常数Pirani gage 皮拉尼计Pirani gage 皮拉尼计Pitch and catch technique 一发一收法Pixel 象素Pixel size 象素尺寸Pixel，display size 象素显示尺寸Planar array 平面阵(列)Plane wave 平面波Plate wave 板波Plate wave technique 板波法Point source 点源Post emulsification 后乳化Post emulsifiable penetrant 后乳化渗透剂Post-cleaning 后清除Post-cleaning 后清洗Powder 粉未Powder blower 喷粉器Powder blower 磁粉喷枪Pre-cleaning 预清理Pressure difference 压力差Pressure dye test 压力着色检测Pressure probe 压力探头Pressure testing 压力检测Pressure- evacuation test 压力抽空检测Pressure mark 压痕Pressure ,design 设计压力Pre-test 初探Primary coil 一次线圈Primary radiation 初级辐射Probe gas 探头气体Probe test 探头检测Probe backing 探头背衬Probe coil 点式线圈Probe coil 探头式线圈Probe coil clearance 探头线圈间隙Probe index 探头入射点Probe to weld distance 探头-焊缝距离Probe/ search unit 探头Process control radiograph 工艺过程控制的射线照相Processing capacity 处理能力Processing speed 处理速度Prods 触头Projective radiography 投影射线透照术Proportioning probe 比例探头Protective material 防护材料Proton radiography 质子射线透照Pulse 脉冲波Pulse 脉冲Pulse echo method 脉冲回波法Pulse repetition rate 脉冲重复率Pulse amplitude 脉冲幅度Pulse echo method 脉冲反射法Pulse energy 脉冲能量Pulse envelope 脉冲包络Pulse length 脉冲长度Pulse repetition frequency 脉冲重复频率Pulse tuning 脉冲调谐Pump- out tubulation 抽气管道Pump-down time 抽气时间Q factor Q值Quadruple traverse technique 四次波法Quality (of a beam of radiation) 射线束的质Quality factor 品质因数Quenching 阻塞Quenching of fluorescence 荧光的猝灭Quick break 快速断间Rad(rad) 拉德Radiance，L 面辐射率，LRadiant existence，M 幅射照度MRadiant flux；radiant power，ψe 辐射通量、辐射功率、ψe Radiation 辐射Radiation does 辐射剂量Radio frequency （r- f）display 射频显示Radio- frequency mass spectrometer 射频质谱仪Radio frequency(r-f) display 射频显示Radiograph 射线底片Radiographic contrast 射线照片对比度Radiographic equivalence factor 射线照相等效系数Radiographic exposure 射线照相曝光量Radiographic inspection 射线检测Radiographic inspection 射线照相检验Radiographic quality 射线照相质量Radiographic sensitivity 射线照相灵敏度Radiographic contrast 射线底片对比度Radiographic equivalence factor 射线透照等效因子Radiographic inspection 射线透照检查Radiographic quality 射线透照质量Radiographic sensitivity 射线透照灵敏度Radiography 射线照相术Radiological examination 射线检验Radiology 射线学Radiometer 辐射计Radiometry 辐射测量术Radioscopy 射线检查法Range 量程Rayleigh wave 瑞利波Rayleigh scattering 瑞利散射Real image 实时图像Real-time radioscopy 实时射线检查法Rearm delay time 重新准备延时时间Rearm delay time 重新进入工作状态延迟时间Reciprocity failure 倒易律失效Reciprocity law 倒易律Recording medium 记录介质Recovery time 恢复时间Rectified alternating current 脉动直流电Reference block 参考试块Reference beam 参考光束Reference block 对比试块Reference block method 对比试块法Reference coil 参考线圈Reference line method 基准线法Reference standard 参考标准Reflection 反射Reflection coefficient 反射系数Reflection density 反射密度Reflector 反射体Refractive index 折射率Refrence beam angle 参考光束角Reicnlbation 网纹Reject; suppression 抑制Rejection level 拒收水平Relative permeability 相对磁导率Relevant indication 相关指示Reluctance 磁阻Rem(rem) 雷姆Remote controlled testing 机械化检测Replenisers 补充剂Representative quality indicator 代表性质量指示器Residual magnetic field/field，residual magnetic 剩磁场Residual technique 剩磁技术Residual magnetic method 剩磁法Residual magnetism 剩磁Resistance （to flow）气阻Resolution 分辨力Resonance method 共振法Response factor 响应系数Response time 响应时间Resultant field 复合磁场Resultant magnetic field 合成磁场Resultant magnetization method 组合磁化法Retentivity 顽磁性Reversal 反转现象Ring-down count 振铃计数Ring-down count rate 振铃计数率Rinse 清洗Rise time 上升时间Rise-time discrimination 上升时间鉴别Rod-anode tube 棒阳极管Roentgen(R) 伦琴Roof angle 屋顶角Rotational magnetic field 旋转磁场Rotational magnetic field method 旋转磁场法Rotational scan 转动扫查Roughing 低真空Roughing line 低真空管道Roughing pump 低真空泵S SSafelight 安全灯Sampling probe 取样探头Saturation，magnetic 磁饱和Saturation level 饱和电平Scan on grid lines 格子线扫查Scan pitch 扫查间距Scanning 扫查Scanning index 扫查标记Scanning directly on the weld 焊缝上扫查Scanning path 扫查轨迹Scanning sensitivity 扫查灵敏度Scanning speed 扫查速度Scanning zone 扫查区域Scattared energy 散射能量Scatter unsharpness 散射不清晰度Scattered neutrons 散射中子Scattered radiation 散射辐射Scattering 散射Schlieren system 施利伦系统Scintillation counter 闪烁计数器Scintillator and scintillating crystals 闪烁器和闪烁晶体Screen 屏Screen unsharpness 荧光增感屏不清晰度Screen-type film 荧光增感型胶片SE probe SE探头Search-gas 探测气体Second critical angle 第二临界角Secondary radiation 二次射线Secondary coil 二次线圈Secondary radiation 次级辐射Selectivity 选择性Semi-conductor detector 半导体探测器Sensitivity va1ue 灵敏度值Sensitivity 灵敏度Sensitivity of leak test 泄漏检测灵敏度Sensitivity control 灵敏度控制Shear wave 切变波Shear wave probe 横波探头Shear wave technique 横波法Shim 薄垫片Shot 冲击通电Side lobe 副瓣Side wall 侧面Sievert(Sv) 希(沃特)Signal 信号Signal gradient 信号梯度Signal over load point 信号过载点Signal overload level 信号过载电平Signal to noise ratio 信噪比Single crystal probe 单晶片探头Single probe technique 单探头法Single traverse technique 一次波法Sizing technique 定量法Skin depth 集肤深度Skin effect 集肤效应Skip distance 跨距Skip point 跨距点Sky shine(air scatter) 空中散射效应Sniffing probe 嗅吸探头Soft X-rays 软X射线Soft-faced probe 软膜探头Solarization 负感作用Solenoid 螺线管Soluble developer 可溶显像剂Solvent remover 溶剂去除剂Solvent cleaners 溶剂清除剂Solvent developer 溶剂显像剂Solvent remover 溶剂洗净剂Solvent-removal penetrant 溶剂去除型渗透剂Sorption 吸着Sound diffraction 声绕射Sound insulating layer 隔声层Sound intensity 声强Sound intensity level 声强级Sound pressure 声压Sound scattering 声散射Sound transparent layer 透声层Sound velocity 声速Source 源Source data label 放射源数据标签Source location 源定位Source size 源尺寸Source-film distance 射线源-胶片距离Spacial frequency 空间频率Spark coil leak detector 电火花线圈检漏仪Specific activity 放射性比度Specified sensitivity 规定灵敏度Standard 标准Standard 标准试样Standard leak rate 标准泄漏率Standard leak 标准泄漏孔Standard test block 标准试块Standardization instrument 设备标准化Standing wave; stationary wave 驻波Step wedge 阶梯楔块Step- wadge calibration film 阶梯楔块校准底片Step- wadge comparison film 阶梯楔块比较底片Step wedge 阶梯楔块Step-wedge calibration film 阶梯-楔块校准片Step-wedge comparison film 阶梯-楔块比较片Stereo-radiography 立体射线透照术Subject contrast 被检体对比度Subsurface discontinuity 近表面不连续性Suppression 抑制Surface echo 表面回波Surface field 表面磁场Surface noise 表面噪声Surface wave 表面波Surface wave probe 表面波探头Surface wave technique 表面波法Surge magnetization 脉动磁化Surplus sensitivity 灵敏度余量Suspension 磁悬液Sweep 扫描Sweep range 扫描范围Sweep speed 扫描速度Swept gain 扫描增益Swivel scan 环绕扫查System examlillatien threshold 系统检验阈值System inclacel artifacts 系统感生物System noise 系统噪声Tackground，target 目标本底Tandem scan 串列扫查Target 耙Target 靶Television fluoroscopy 电视X射线荧光检查Temperature envelope 温度范围Tenth-value-layer(TVL) 十分之一值层Test coil 检测线圈Test quality level 检测质量水平Test ring 试环Test block 试块Test frequency 试验频率Test piece 试片Test range 探测范围Test surface 探测面Testing，ulrasonic 超声检测Thermal neutrons 热中子Thermocouple gage 热电偶计Thermogram 热谱图Thermography，infrared 红外热成象Thermoluminescent dosemeter(TLD) 热释光剂量计Thickness sensitivity 厚度灵敏度Third critiical angle 第三临界角Thixotropic penetrant 摇溶渗透剂Thermal resolution 热分辨率Threading bar 穿棒Three way sort 三档分选Threshold setting 门限设置Threshold fog 阈值灰雾Threshold level 阀值Threshotd tcnet 门限电平Throttling 节流Through transmission technique 穿透技术Through penetration technique 贯穿渗透法Through transmission technique; transmission technique 穿透法Through-coil technique 穿过式线圈技术Throughput 通气量Tight 密封Total reflection 全反射Total image unsharpness 总的图像不清晰度Tracer probe leak location 示踪探头泄漏定位Tracer gas 示踪气体Transducer 换能器/传感器Transition flow 过渡流Translucent base media 半透明载体介质Transmission 透射Transmission densitomefer 发射密度计Transmission coefficient 透射系数Transmission point 透射点Transmission technique 透射技术Transmittance，τ 透射率τTransmitted film density 检测底片黑度Transmitted pulse 发射脉冲Transverse resolution 横向分辨率Transverse wave 横波Traveling echo 游动回波Travering scan; depth scan 前后扫查Triangular array 正三角形阵列Trigger/alarm condition 触发/报警状态Trigger/alarm level 触发/报警标准Triple traverse technique 三次波法True continuous technique 准确连续法技术Trueattenuation 真实衰减Tube current 管电流Tube head 管头Tube shield 管罩Tube shutter 管子光闸Tube window 管窗Tube-shift radiography 管子移位射线透照术Two-way sort 两档分选Ultra- high vacuum 超高真空Ultrasonic leak detector 超声波检漏仪Ultrasonic noise level 超声噪声电平Ultrasonic cleaning 超声波清洗Ultrasonic field 超声场Ultrasonic flaw detection 超声探伤Ultrasonic flaw detector 超声探伤仪Ultrasonic microscope 超声显微镜Ultrasonic spectroscopy 超声频谱Ultrasonic testing system 超声检测系统Ultrasonic thickness gauge 超声测厚仪Ultraviolet radiation 紫外辐射Under development 显影不足Unsharpness 不清晰Useful density range 有效光学密度范围UV-A A类紫外辐射UV-A filter A类紫外辐射滤片Vacuum 真空Vacuum cassette 真空暗盒Vacuum testing 真空检测Vacuum cassette 真空暗合Van de Graaff generator 范德格喇夫起电机Vapor pressure 蒸汽压Vapour degreasing 蒸汽除油Variable angle probe 可变角探头Vee path V型行程Vehicle 载体Vertical linearity 垂直线性Vertical location 垂直定位Visible light 可见光Vitual image 虚假图像V oltage threshold 电压阈值V oltage threshold 阈值电压Wash station 水洗工位Water break test 水膜破坏试验Water column coupling method 水柱耦合法Water column probe 水柱耦合探头Water path; water distance 水程Water tolerance 水容限Water-washable penetrant 可水洗型渗透剂Wave 波Wave guide acoustic emission 声发射波导杆Wave train 波列Wave from 波形Wave front 波前Wave length 波长Wave node 波节Wave train 波列Wedge 斜楔Wet slurry technique 湿软磁膏技术Wet technique 湿法技术Wet method 湿粉法Wetting action 润湿作用Wetting action 润湿作用Wetting agents 润湿剂Wheel type probe; wheel search unit 轮式探头White light 白光White X-rays 连续X射线Wobble 摆动Wobble effect 抖动效应Working sensitivity 探伤灵敏度Wrap around 残响波干扰Xeroradiography 静电射线透照术X-radiation X射线X-ray controller X射线控制器X-ray detection apparatus X射线探伤装置X-ray film 射线胶片X-ray paper X射线感光纸X-ray tube X射线管X-ray tube diaphragm X射线管光阑Yoke 磁轭Yoke magnetization method 磁轭磁化法Zigzag scan 锯齿扫查Zone calibration location 时差区域校准定位。
光纤通信中需要掌握的英文单词及缩写
光纤通信中常用英文缩写ac alternating current 交变电流AM amplitude modulation 幅度调制APD avalanche photodiode 雪崩二极管ASE amplified spontaneous emission 放大自发辐射ASK amplitude shift keying 幅移键控BER bit error rate 误码率CATV common antenna cable television 有线电视CDM code division multiplexing 码分复用CNR carrier to noise ratio 载噪比CVD chemical vapour deposition 化学汽相沉积CW continuous wave 连续波DBR distributed Bragg reflector 分布布拉格反射DFB distributed feedback 分布反馈dc direct current 直流DCF dispersion compensating fiber 色散补偿光纤DSF dispersion shift fiber 色散位移光纤DIP dual in line package 双列直插EDFA erbium doped fiber amplifier 掺铒光纤激光器FDDI fiber distributed data interface 光纤数据分配接口FP Fabry Perot 法布里- 珀罗FWHM full width at half maximum 半高全宽FWM four-wave mixing 四波混频GVD group-velocity dispersion 群速度色散IM/DD intensity modulation with direct detection 强度调制直接探测LED light emitting diode 发光二极管L-I light current 光电关系MCVD Modified chemical vapor deposition 改进的化学汽相沉积MZ mach-Zehnder 马赫泽德NA numerical aperture 数值孔径NF noise figure 噪声指数NRZ non-return to zero 非归零OC optical carrier 光载波OOK on-off keying 开关键控OTDM optical time-division multiplexing 光时分复用OVD outside-vapor deposition 轴外汽相沉积OXC optical cross-connect 光交叉连接PCM pulse-code modulation 脉冲编码调制PDM polarization-division multiplexing 偏振复用PON passive optical network 无源光网络RZ return-to-zero 归零RA raman amplifier 拉曼放大器SBS stimulated Brillouin scattering 受激布里渊散射SCM subcarrier multiplexing 副载波复用SDH synchronous digital hierarchy 同步数字体系SLA/SOA semiconductor laser/optical amplifier 半导体激光器/光放大器SLM single longitudinal mode 单纵模SNR signal-to-noise ratio 信噪比SONET synchronized optical network 同步光网络SRS stimulated Raman scattering 受激拉曼散射TCP/IP transmission control protocol/internet protocol 传输控制协议/ 互联网协议TDM time-division multiplexing 时分复用TW traveling wave 行波VAD vapor-axial epitaxy 轴向汽相沉积VCSEL vertical-cavity surface-emitting laser 垂直腔表面发射激光器VPE vapor-phase epitaxy 汽相沉积WDMA wavelength-division multiple access 波分复用接入系统DWDM dense wavelength division multiplexing/multiplexer密集波分复用/ 器FBG fiber-bragg grating 光纤布拉格光栅AWG arrayed-waveguide grating 阵列波导光栅LD laser diode 激光二极管AOTF acousto optic tunable filter 声光调制器AR coatings antireflection coatings 抗反膜SIOF step index optical fiber 阶跃折射率分布光纤GIOF graded index optical fiber 渐变折射率分布光纤Cross-talk 串音Passive component 无源器件Active component 有源器件Soliton 孤子Jitter 抖动Heterodyne 外差Homodyne 零差Transmitter 发射机Receiver 接收机Transceiver module 收发模块Birefringence 双折射Chirp 啁啾Binary 二进制Chromatic dispersion 色度色散Cladding 包层Jacket 涂层Core cladding interface 纤芯包层界面Gain-guided semiconductor laser 增益导引半导体激光器Index-guide semiconductor laser 折射率半导导引体激光器Threshold 阈值Power penalty 功率代价Dispersion 色散Attenuation 衰减Nonlinear optical effect 非线性效应Polarization 偏振Double heterojunction 双异质结Electron-hole recombination 电子空穴复合Linewidth 线宽Preamplifer 前置放大器Inline amplifier 在线放大器Power amplifier 功率放大器Extinction ratio 消光比Eye diagram 眼图Fermi level 费米能级Multimode fiber 多模光纤Block diagram 原理图Quantum limited 量子极限Intermode dispersion 模间色散Intramode dispersion 模内色散Filter 滤波器Directional coupler 定向耦合器Isolator 隔离器Circulator 环形器Detector 探测器Laser 激光器Polarization controller 偏振控制器Attenuator 衰减器Modulator 调制器Optical switch 光开关Lowpass filter 低通滤波器Highpass filter 高通滤波器Bandpass filter 带通滤波器Longitudinal mode 纵模Transverse mode 横模Lateral mode 侧模Sensitivity 灵敏度Quantum efficiency 量子效率White noise 白噪声Responsibility 响应度Waveguide dispersion 波导色散Zero-dispersion wavelength 零色散波长Free spectral range 自由光谱范围Surface emitting LED 表面发射LED Edge emitting LED 边发射LED Thermal noise 热噪声Quantum limit 量子极限Sensitivity degradation 灵敏度劣化Intensity noise 强度噪声Timing jitter 时间抖动Packaging 封装Maxwell’s equations 麦克斯韦方程组Material dispersion 材料色散Rayleigh scattering 瑞利散射Nonradiative recombination 非辐射复合Driving circuit 驱动电路Sketch 绘图Splice 接续r efractive index 折射率cladding 包层modal distortion 模式畸变GRIN fibers 渐变折射率光纤Multimode 多模SI fibers 阶跃折射率光纤Spontaneous emission 自发辐射APD 雪崩光电二极管Sensitivity 灵敏度statistical law 统计规律threshold current 阈值电流forward biased 正向偏置reverse biased 反向偏置Edge emitting LED 边发射二极管Surface emitting LED 面发射二极管Lambertian pattern 朗伯型Visible 可见infrared 红外ultraviolet 紫外carrier 载波resonant 谐振F-P Lasers 法布里-珀罗激光器longitudinal modes 纵模transverse modes 横模Population inversion 离子数反转Stimulated emission 受激辐射Positive feedback正反馈excess lose 额外损耗splice 接续depletion region 耗尽层transit time 渡越时间response time 响应时间attenuation 衰减scattering 散射bandgap 能带间隙cutoff wavelength 截止波长star couplers 星型耦合器fiber Bragg grating 光纤布拉格光栅fiber optical isolator 光纤隔离器switches 光开关linearly polarized 线偏振circularly polarized 圆偏振unpolarized 非偏振WDM 波分复用Photodetector 光探测器Photon 光子EDF，Erbium Doped Fiber 掺铒光纤EDFA 掺铒光纤放大器energy level diagram 能级图electroabsorption modulator 电吸收调制器external modulation 外调制internal modulation 内调制quantum efficiency 量子效率slope efficiency 斜率效率pump wavelength 泵浦波长spectral width 谱宽silica fibers 石英光纤V ：归一化频率source linewidth 光源线宽optic bandwidth 光带宽electrical bandwidth. 电带宽chirp 啁啾analog modulation 模拟调制digital modulation 数字调制transparent windows 透光窗口attenuation coefficient 衰减系数SNR，signal-to-noise ratio 信噪比noise figure 噪声指数responsivity 响应度。
节点中介性和频谱离散度感知虚拟光网络生存性协同映射
节点中介性和频谱离散度感知虚拟光网络生存性协同映射刘焕淋*① 胡会霞① 陈 勇② 温 濛① 王展鹏①①(重庆邮电大学通信与信息工程学院 重庆 400065)②(重庆邮电大学自动化学院 重庆 400065)摘 要：虚拟网络的映射策略影响弹性光网络(EON)资源可用性和网络生存性。
该文提出一种基于节点间距离和频谱离散度感知的虚拟光网络生存性协同映射(CM-DSDA)算法，研究节点计算资源和拓扑位置中介性的光节点排序策略，设计频谱离散度方法评价链路频谱碎片化程度。
在虚拟链路的生存性映射中，选择邻接已映射节点中消耗频隙数少且频谱离散度低的工作光路和保护光路协同映射虚拟网络。
仿真结果表明所提算法能有效地提高EON 的频谱占用率和减少带宽阻塞率。
关键词：虚拟光网络；生存性协同映射；节点中介性；频谱离散度；频谱占用率中图分类号：TN929.11文献标识码：A文章编号：1009-5896(2020)09-2166-07DOI : 10.11999/JEIT190543Survivability Coordinated Mapping Based on Node Centrality and Spectrum Dispersion Awareness for Virtual Optical NetworksLIU Huanlin ① HU Huixia ① CHEN Yong ② WEN Meng ① WANG Zhanpeng ①①(School of Communication and Information Engineering , Chongqing University of Postsand Telecommunications , Chongqing 400065, China )②(School of Automation , Chongqing University of Posts and Telecommunications , Chongqing 400065, China )Abstract : The mapping strategy of virtual network has important effect on the resource availability and survivability of the Elastic Optical Network (EON). A survivable virtual optical network Coordinated Mapping based on the Distance and Spectrum Dispersion Awareness (CM-DSDA) between nodes is proposed in the paper. A physical node weighted sorting strategy is studied, which not only considers the number of physical node computing resources, but also considers the location centrality of the physical nodes in the EON topology.And a method of spectrum dispersion is designed to evaluate the link’s spectrum fragmentation. During the virtual link’s survivability mapping, the working and protection optical paths adjacent the position of the mapped physical nodes with the minimum number of spectrum usage and the lowest frequency spectrum dispersion are selected to coordinated mapping the virtual optical networks. Simulation results show that the CM-DSDA can effectively increase the EON’s spectrum utilization and reduce bandwidth blocking probability.Key words : Virtual optical network; Survivable coordinated mapping; Node centrality; Spectrum dispersion;Spectrum usage ratio1 引言随着云计算、移动互联网、未来网等数据应用快速发展，网络中海量数据的交换和不确定性流向对传统的带宽固定、调制格式单一的波分复用光网络提出了挑战[1]。
envi的radiometric calibration工具原理 -回复
envi的radiometric calibration工具原理-回复Radiometric calibration is an essential process in remote sensing and satellite imaging, which aims to ensure the accurate measurement of radiometric values from an image. The calibration process corrects any uncertainties or variations caused by sensor characteristics, atmospheric conditions, and other factors. ENVIRadiometric Calibration (ENVIRadCal) is a tool developed by Exelis Visual Information Solutions (Exelis VIS) for radiometric calibration. In this article, we will explore the principles and steps involved in ENVIRadCal.Principle of Radiometric Calibration:Radiometric calibration is based on the concept of converting digital numbers (DN) acquired by a sensor into physical values such as radiance or reflectance. The goal is to establish a quantitative relationship between the digital numbers and the actual radiometric properties of the scene.Step 1: Sensor CharacterizationThe first step in radiometric calibration is to characterize the sensor's response through laboratory measurements. This process is known as sensor calibration. It involves measuring the sensor'sspectral response, linearity, saturation levels, and gain levels under controlled conditions. These measurements are done using calibrated radiation sources and specific calibration techniques. The output of sensor calibration is a set of calibration coefficients that relate the digital numbers acquired by the sensor to the actual radiometric values measured by the calibration devices.Step 2: Atmospheric CorrectionThe next step is atmospheric correction, which accounts for the influence of atmospheric scattering and absorption on the measured radiance. This step is crucial because the atmosphere can significantly affect the radiometric values received by the sensor. Atmospheric correction algorithms estimate and remove the atmospheric effects, allowing an accurate measurement of the surface reflectance or radiance. Several methods are available for atmospheric correction, including models based on physical principles, empirical models, and data-driven methods.Step 3: Calibration ValidationAfter atmospheric correction, the radiometric values are usually compared to ground measurements or other reference data to validate the calibration accuracy. This step helps identify anysystematic biases or errors and allows for fine-tuning the calibration coefficients if necessary. The validation can be performed using field spectroradiometers, ground targets, or reference data from other sensors or satellite missions.Step 4: Image RectificationBefore applying the radiometric calibration to the entire image or dataset, it is necessary to rectify the image to a uniform and consistent coordinate system. Image rectification corrects geometric distortions, such as terrain relief, sensor position and orientation, Earth curvature, and spacecraft motion. This step ensures that each pixel in the image corresponds to a known location on the Earth's surface, facilitating accurate radiometric calibration.Step 5: Applying Radiometric CalibrationOnce the image is rectified, the radiometric calibration coefficients obtained from sensor characterization are applied to the digital numbers of the image. This step converts the calibrated digital numbers into radiometric values such as radiance or reflectance. The radiometric calibration algorithm uses the calibration coefficients to adjust the DN values according to the sensor'sresponse and the atmospheric conditions.Step 6: Evaluation and Quality ControlAfter applying radiometric calibration, it is essential to evaluate the quality of the calibrated image. This evaluation includes assessing various image quality parameters, such as signal-to-noise ratio, radiometric accuracy, spatial resolution, and spectral fidelity. Quality control techniques, such as visual inspection, statistical analysis, and comparison with ground truth data, can be employed to ensure the accuracy and reliability of the radiometric calibration.ENVIRadCal: An OverviewENVIRadCal is a comprehensive radiometric calibration tool provided by Exelis VIS. It seamlessly integrates the above steps with a user-friendly interface, enabling users to perform radiometric calibration in a streamlined manner. ENVIRadCal incorporates sensor-specific calibration information, atmospheric correction algorithms, and image rectification capabilities. It also supports the evaluation of calibration quality and provides advanced visualization tools for result analysis.In conclusion, radiometric calibration is a crucial process in remotesensing and satellite imaging to ensure accurate and reliable radiometric measurements. The ENVIRadCal tool by Exelis VIS provides an effective and efficient solution for performing radiometric calibration. By following the steps outlined above, users can achieve accurate and calibrated radiometric values for their remote sensing applications.。
sora实现原理
sora实现原理SORA (Secure Open Radio Access) is a protocol designed to enable efficient and secure communication in wireless networks, particularly in the context of 5G and beyond. The implementation principles of SORA typically involve the following key aspects:1.Decentralization: SORA emphasizes a decentralizedapproach to wireless communication, allowing devices tocommunicate directly with each other without relying heavily oncentralized infrastructure. This decentralization enhancesscalability, resilience, and flexibility in network deployment.2.Dynamic Spectrum Access: SORA enables dynamicspectrum access, allowing devices to opportunistically utilizeavailable spectrum bands efficiently. This is particularly important in the context of spectrum scarcity and increasing demand forwireless communication services.3.Security and Privacy: SORA prioritizes security andprivacy in wireless communication by incorporating robustencryption mechanisms, authentication protocols, and privacy-preserving techniques. This ensures that sensitive informationremains protected and that communication channels are securefrom malicious attacks.4.Resource Efficiency: SORA aims to optimize theutilization of network resources, including spectrum, power, and bandwidth, to improve overall network efficiency and performance. By dynamically adapting to changing network conditions, SORA maximizes resource utilization while minimizing interference and congestion.5.Interoperability: SORA is designed to be compatible with existing wireless communication standards and protocols, facilitating interoperability with heterogeneous networks and devices. This ensures seamless integration and compatibility with legacy systems, enabling smooth migration to SORA-based solutions.6.Adaptability and Flexibility: SORA provides mechanisms for adaptive and flexible communication, allowing devices to adjust their communication parameters dynamically based on environmental conditions, network congestion, and user requirements. This adaptability enhances the reliability and resilience of wireless networks in diverse deployment scenarios.7.Openness and Collaboration: SORA promotes openness and collaboration among stakeholders, including researchers, industry partners, and regulatory bodies, to foster innovation, standardization, and the development of interoperable solutions. This collaborative approach accelerates the adoption andevolution of SORA in wireless communication ecosystems.描述（Chinese description）：SORA（安全开放无线接入）是一种旨在实现无线网络中高效安全通信的协议，特别是在5G及其之后的环境中。
纹理物体缺陷的视觉检测算法研究--优秀毕业论文
摘 要
在竞争激烈的工业自动化生产过程中，机器视觉对产品质量的把关起着举足 轻重的作用，机器视觉在缺陷检测技术方面的应用也逐渐普遍起来。与常规的检 测技术相比，自动化的视觉检测系统更加经济、快捷、高效与 安全。纹理物体在 工业生产中广泛存在，像用于半导体装配和封装底板和发光二极管，现代 化电子 系统中的印制电路板，以及纺织行业中的布匹和织物等都可认为是含有纹理特征 的物体。本论文主要致力于纹理物体的缺陷检测技术研究，为纹理物体的自动化 检测提供高效而可靠的检测算法。 纹理是描述图像内容的重要特征，纹理分析也已经被成功的应用与纹理分割 和纹理分类当中。本研究提出了一种基于纹理分析技术和参考比较方式的缺陷检 测算法。这种算法能容忍物体变形引起的图像配准误差，对纹理的影响也具有鲁 棒性。本算法旨在为检测出的缺陷区域提供丰富而重要的物理意义，如缺陷区域 的大小、形状、亮度对比度及空间分布等。同时，在参考图像可行的情况下，本 算法可用于同质纹理物体和非同质纹理物体的检测，对非纹理物体 的检测也可取 得不错的效果。 在整个检测过程中，我们采用了可调控金字塔的纹理分析和重构技术。与传 统的小波纹理分析技术不同，我们在小波域中加入处理物体变形和纹理影响的容 忍度控制算法，来实现容忍物体变形和对纹理影响鲁棒的目的。最后可调控金字 塔的重构保证了缺陷区域物理意义恢复的准确性。实验阶段，我们检测了一系列 具有实际应用价值的图像。实验结果表明 本文提出的纹理物体缺陷检测算法具有 高效性和易于实现性。 关键字: 缺陷检测；纹理；物体变形；可调控金字塔；重构
Keywords: defect detection, texture, object distortion, steerable pyramid, reconstruction
II
PSL-603U调试手册(智能站)国网版本V1.0
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修订日期 20术部
PSL-603U 智能站调试手册
目 录 版本说明.......................................................................................................................................................................................................... - 2 目 录................................................................................................................................................................................................................ - 3 1. 现场信息确认.....................................................................................
中英翻译《使用加权滤波器的一种改进的谱减语音增强算法》
使用加权滤波器的一种改进的谱减语音增强算法摘要在噪声环境，例如飞机座舱、汽车引擎中，语音中或多或少地夹杂着噪声。
为了减少带噪语音中的噪声，我们提出了一种改进型的谱减算法。
这种算法是利用对谱减的过度减法而实现的。
残余噪声能够利用人类听觉系统的掩蔽特性被掩蔽。
为了消除残余的音乐噪声，引入了一种基于心理声学的有用的加权滤波器。
通过仿真发现其增强的语音并未失真，而且音乐噪声也被有效地掩蔽，从而体现了一种更好的性能。
关键词：语音增强；谱减1.引言语音信号中经常伴有环境中的背景噪声。
在一些应用中如：语音命令系统，语音识别，说话者认证，免提系统，背景噪声对语音信号的处理有许多不利的影响。
语音增强技术可以被分为单通道和多通道或多通道增强技术。
单通道语音增强技术的应用情况是只有一个采集通道可用。
谱减语音增强算法是一个众所周知的单通道降噪技术[]2,1。
大多数实现和多种基本技术的运用是在语音谱上减去对噪声谱的估计而得以实现的。
传统的功率谱相减的方法大大减少了带噪语音中的噪声水平。
然而，它也在语音信号中引入了一种被称为音乐噪声的恼人的失真。
在本文中我们运用一种能够更好、更多地抑制噪声的改进的频谱过度减法的方法[]3。
该方法的运用是为了估计纯净语音的功率谱，它是通过从语音功率谱中减去噪声功率谱的过度估计而实现的。
此外，为了在语音失真和噪声消除之间找到最佳的平衡点，一种基于声学心理学的动机谱加权规则被纳入。
通过利用人耳听觉系统的掩蔽特性能够掩蔽现有的残余噪声。
当确定了语音掩蔽阈值的时候，运用一种改进的掩蔽阈值估计来消除噪声的影响。
该方法提供了比传统的功率谱相减法更优越的性能，并能在很大程度上降低音乐噪声。
2．过度谱相减算法该方法的基本假设是把噪声看作是独立的加性噪声。
假设已经被不相关的加性噪声信号()t n降解的语音信号为()t s：()()()t n t s t x += （1）带噪语音信号的短时功率谱近似为：()()()ωωωj j j e N e S e X +≈ （2） 通过用无音期间得到的平均值()2ωj e N 代替噪声的平方幅度值()2ωj e N 得到功率谱相减的估计值为： ()()()222ˆωωωj j j e N e X e S -= （3）在运用了谱减算法之后，由于估计的噪声和有效噪声之间的差异而出现了一种残余噪声。
核磁共振波谱仪降场
核磁共振波谱仪降场Decommissioning of Nuclear Magnetic Resonance SpectrometerWith the advancement of technology, the decommissioning of outdated scientific instruments including nuclear magnetic resonance (NMR) spectrometers has become a common practice. NMR spectrometers, which were once the cutting-edge equipment in many research laboratories, require periodic upgrades to keep up with the rapidly evolving scientific community's needs. As a result, the decommissioning process of these instruments has gained significance.The decommissioning of an NMR spectrometer involves several steps to ensure its safe and environmentally friendly removal. Firstly, a thorough assessment is conducted to determine the condition of the instrument, including its functionality, overall performance, and compatibility with modern software and hardware systems. If the instrument is deemed outdated or unfit for further use, the decision to decommission is made.The next step involves proper disposal of hazardous materials. NMR spectrometers often contain substances such as coolant fluids, refrigerants, and sometimes radioactive isotopes. These substances are potentially harmful to the environment and require careful handling. Professional disposal services are employed to ensure their safe removal and destruction, adhering to all applicable regulations and guidelines.Following the disposal of hazardous materials, the physical deconstruction of the NMR spectrometer begins. This process requires skilled technicians who possess the knowledge and experience to dismantle the instrument without causing damage to surrounding equipment or compromising safety. The deconstruction process also involves separating various components of the spectrometer, such as magnets, coils, and electronics, to facilitate proper recycling or disposal.Once the instrument has been dismantled, the leftover materials are sorted based on their recyclability. For instance, magnets can be recovered for reuse, while metals and plastics are recycled or disposed of appropriately. It is essential to follow proper recycling protocols to minimize waste and reduce the impact on the environment.Lastly, after the decommissioning process, the laboratory space where the NMR spectrometer was located must undergo thorough cleaning and decontamination. This ensures that any residual hazardous materials or contaminants are safely removed and the area can be repurposed for other scientific research.In conclusion, the decommissioning of NMR spectrometers has become necessary due to advancements in technology and the need for upgraded instruments in research laboratories. Proper disposal of hazardous materials, skillful deconstruction, recycling, and decontamination are essential steps in the decommissioning process of these instruments. By adhering to these procedures, research laboratories can ensure the safe and environmentally responsible removal of NMR spectrometers.。
【高分子专业英语翻译】
【高分子专业英语翻译】第五课乳液聚合大部分的乳液聚合都是由自由基引发的并且表现出其他自由基体系的很多特点,最主要的反应机理的不同源自小体积元中自由基增长的场所不同。
乳液聚合不仅允许在高反应速率下获得较高分子量,这在本体聚合中是无法实现或效率低下的,,同时还有其他重要的实用优点。
水吸收了大部分聚合热且有利于反应控制,产物在低粘度体系中获得,容易处理,可直接使用或是在凝聚,水洗,干燥之后很快转化成固体聚合物。
在共聚中,尽管共聚原理适用于乳液体系,单体在水相中溶解能力的不同也可能导致其与本体聚合行为不同,从而有重要的实际意义。
乳液聚合的变化很大,从包含单一单体,乳化剂,水和单一引发剂的简单体系到这些包含有2,3个单体,一次或分批添加,,混合乳化剂和助稳定剂以及包括链转移剂的复合引发体系。
单体和水相的比例允许变化范围很大,但是在技术做法上通常限制在30/70到60/40。
单体和水相比更高时则达到了直接聚合允许的极限,只有通过分批添加单体方法来排除聚合产生的大量的热。
更复杂的是随着胶体数的增加粘度也大大增加,尤其是当水溶性的单体和聚合物易容时,反应结束胶乳浓度降低。
这一阶段常常伴随着通过聚集作用或是在热力学不稳定时凝结作用而使胶粒尺寸增大。
第十课高分子的构型和构象本课中我们将使用根据经典有机化学术语而来的构型和构象这两个词。
构型异构是由于分子中存在一个或多个不对称中心,以最简单的C原子为例,每一碳原子的绝对构型为R型和S型,当存在双键时会有顺式和反式几何异构。
以合成聚合物为例,构型异构的典型问题和R.S型不对称碳原子在主链上的排布有关。
这些不对称碳原子要么来自不对称单体,如环氧丙烷,要么来自对称单体,如乙烯单体,,这些物质的聚合,在每个单体单元中形成至少一个不对称碳原子。
大分子中的构型异构源于侧链上存在不对称的碳原子,例如不对称乙烯单体的聚合,也是可能的,现今已经被广泛研究。
和经典有机化学术语一致,构象,旋转体,旋转异构体,构象异构体,指的是由于分子单键的内旋转而形成的空间排布的不同。
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Abstract- This paper presents a framework to achieve an efficient dynamic and decentralized spectrum and radio resource usage in heterogeneous wireless network scenarios. The envisaged technical solution follows a layered approach, where Joint Radio Resource Management (JRRM) and Advanced Spectrum Management (ASM) mechanisms are identified at both intra and inter-operator level. The importance of cognitive network functionalities is highlighted. An on-demand Cognitive Pilot Channel (CPC) is proposed as a radio enabler solution for a decentralized operation with decision making processes executed at the mobile terminal side. The suitability of the proposed solution is shown by comparison with a broadcast CPC approach.
Decentralized Spectrum and Radio Resource Management Enabled by an On-demand Cognitive
Pilot Channel
O. Sallent, R. Agustí, J. Pérez-Romero, L. Giupponi
The framework envisaged above, characterized by a multiplicity of Radio Access Technologies (RATs) empowered by flexible spectrum capabilities, can only be fully accomplished by further enhancing the Radio Access Networks (RANs) towards Cognitive Networks complemented with Cognitive Radio-based technologies. On one hand, a cognitive network exploits a process that can
Indeed, numerous studies support the observation that the usage of radio resource spectrum experiences significant fluctuations. Usually, heavy spectrum utilization takes place in unlicensed bands while some licensed bands often experience low (e.g. TV bands) or medium utilization. Based on these considerations, the TV band Notice of Proposed Rule Making (NPRM) [3] was the natural next step taken by the FCC. The proposition of the NPRM allows unlicensed radios to operate in the TV broadcast bands if no harmful interference is caused to incumbent services (e.g., TV receivers). These events culminated in the formation of the IEEE 802.22, developing an air interface for unlicensed operation in the TV broadcast bands [4].
Several works in the literature have recently dealt with flexible spectrum management strategies. In [5] the DIMSUMNet architecture is presented for coordinated, realtime dynamic spectrum access based on a centralized entity called Spectrum Broker as opposite to other opportunistic, uncoordinated methods. The concepts of coordinated access band and statistically multiplexed access to spectrum are introduced. Further work on this topic is presented in [6], where different formulations for solving the spectrum allocation problem based on linear programming are presented. In [7] a spectrum etiquette protocol for efficient coordination of radio communication devices in d frequency bands using different radio technologies is proposed. It uses a common protocol for the announcement of radio and service parameters.
for spectrum and the requirement that the spectrum is used more efficiently [1]. For this purpose, a narrow view would be to look to technology as a mean to provide more robust communications systems with increased efficiency. Instead, a broader view is to examine spectrum utilization from a time/location/band/power perspective as suggested in the Federal Communications Commission Spectrum Policy Task Force Report [2].
I. INTRODUCTION
It is widely acknowledged that technological innovation has a relevant impact on economic growth. In turn, wireless communications are a key driver for the stimulation of economies, building social networks and facilitating a sustainable development, to the point that wireless communications are nowadays an integral part of modern living. Not surprisingly, wireless technologies are rapidly evolving in order to allow operators delivering more advanced multimedia services to their customers. For example, HSDPA (High Speed Downlink Packet Access) and HSUPA (High Speed Uplink Packet Access) are seen as intermediate evolutionary steps since the first wave of WCDMA-based (Wideband Code Division Multiple Access) networks rollout, E-UTRAN (Evolved UMTS Terrestrial Radio Access Network) being the long term perspective for the 3GPP technology family both in terms of new architecture and radio access technologies. Similar paths are drawn from the 3GPP2 around the evolution of CDMA2000. On the other hand, the IEEE 802 is producing an evolving family of standards, such as 802.11 local, 802.15 personal, 802.16 and 802.20 metropolitan and 802.22 regional area networks. Furthermore, the regulatory perspective on how the spectrum should be allocated and utilized in such a complex and heterogeneous technology scenario is evolving as well. The evolution is towards a cautious introduction of more flexibility in spectrum management together with economic considerations on spectrum trading. This new spectrum management paradigm is driven by the growing competition