频域测量

本文介绍中国计量科学研究院（NIM）在相位噪声频域测量方面的最新进展，叙述了系统的性能，详细讨论了测量不确定度，指出系统的噪声本底小于-170dBc/Hz。

The current advance on the phase noise measurement in the frequency domain in NIM (?) s presented . THe performance of the system is described .

利用相干渡越辐射（CTR）测量短和超短电子束团长度是国际上束测领域新发展的频域测量技术。

Measurement of electron bunch length through its generated CTR is a new frequency domain technique developed in the accelerator and FEL fields recently .

通过比较仿真结果，在FPGA实现时选则了一种精度较高的方法&频域测量法，该方法的巧妙之处在于利用了频谱峰值的相位。

Accord - ing to the comparison to the simulation results , a method with relatively high accuracy & frequency domain distance measuring method is chosen in the FPGA implementation . The method make use of the phase of FFT peak value .

利用相干衍射辐射（CDR）光学自相关技术在线无阻拦频域测量超短电子束团的长度是当前国际束测领域的研究热点。

Measurement of electron bunch length through its generated coherent diffraction radiation ( CDR ) via optical autocorrelation is a new non-intercepting frequency domain diagnostics technique developed in accelerator fields recently .

腐蚀金属电极的电化学频域测量研究进展&金属腐蚀与防护研究所电化学研究介绍之一

Electrochemical Studies on Corroding Metallic Electrodes in Frequency Domain

相位噪声自动频域测量系统及其不确定度估计

A Phase Noise Automatic Measurement System in the Frequency Domain and Its Uncertainty Estimation

频域测量中的慢极化效应

Slow Polarization Effect in Frequency Domain Measurement

交流变频腐蚀动力学参数的时频域测量方法

A New Measurement of Kinetic Factor in AC Variable Frequency Corrosion Study Based on Time-frequency Analysis

又因为电力系统会随著时间而有所变动，此类的频域测量方法无法观察到相对于时间的变化。

Besides , frequency-domain methods will not represent the time-dependent phenomenon if the signal varies with time .

这种方法利用频域测量矩阵直接给出了圆度形状误差和回转误差的最小二乘解或最小均方误差解。

The least square solution and minimum mean square error ( MMSE ) solution for roundness error and spindle error was derived by measurement matrix in frequency-domain .

针对建立室内信道测量系统的需要，总结了信道测量的各类方法，提出了室内信道时域和频域测量的完整的系统方案。

The methods of channel measurement were overviewed and the complete schemes in time domain and frequency domain were proposed for establishing measurement system for indoor channels .

该方法将非线性产生的谐波考虑在内，因而可以分析电路的非线性特性。我们利用黑箱模型分析非线性特性，该方法是在基于频域测量的基础上建立的。

The method takes the influence of harmonic waves into account , so it can be used for the analysis of nonlinear characteristic . A black-box model based on frequency domain measurement is introduced .

本文给出测试系统原理图、脉间频率和相位稳定度测量方法以及时域、频域测量结果。

This paper gives the principle diagrams of the measurement system and some methods of measuring the stability of inter pulse frequency and phase . The measurement results in time and frequency domains are given .

小波神经网络建模法是基于频域测量的，本文介绍了非线性器件在真实的大信号工作条件下测量的解决方案，搭建了非线性散射函数的测试系统，通过校准和测试获得了大量数据。

In this paper , we introduce how to measure devices in a real large signal situation , how to set up a test system of nonlinear scattering . Then a large amounts of data of calibration and test are obtained .

该方法是一种频域测量法，可以在频域上有效的滤除气溶胶产生的米氏散射干扰，同时大气布里渊频移严格正比于大气温度的平方根，因而具有更高的精度。

This approach is based on frequency domain and the disturbance of Mie scattering can be avoided effectively . This approach has a high accuracy because there is a one - to - one correspondence between the atmospheric temperature and Brillouin shift frequency .

该文以几何绕射模型为基础，综合利用多频段的频域测量数据，给出了散射中心位置、幅度和散射类型参数的融合估计方法。

Based on the GTD ( Geometrical Theory of Diffraction ) parametric model , this paper presents a novel method which can synthetically apply the multi-band measurements in frequency domain and effectively estimate the parameters of scatterers , including location , amplitude and scattering type .

本文着重介绍频域法测量CATV同轴电缆回波损耗的方法，并对某些波形进行分析，提出改进建议。

This paper focuses on the return loss measurement methods for CATV cables , of which frequency domain method is chosen . In addition , some waveforms are analyzed and some suggestions for improvement are given .

其中利用电力环网线路直接测量信道传输函数H（f）的幅频响应和相频响应的新方法，解决了一直难以处理的长距离物理信道相频响应频域直接测量的问题。

And a new approach which uses the electrical loop wires to directly measure the channel transfer function H ( f ) and obtains the amplitude response and phase response , is provided to deal with the direct measurement of phase response for a line of long length .

实验表明：修正后的时域数据与频域直接测量结果非常吻合。

Some experiments have showed that the corrected time domain data agree well with the measuring results directly in the frequency domain .

激发极化发就是利用衰减现象来进行时间域方法测量，利用电阻率差异现象来进行频域方法测量。

Induced polarization surveys are made by the time-domain method , using the decay phenomenon , and by the frequency-domain method , using the resistivity contrast phenomenon .

随着微电子技术、信号处理技术和计算机技术的迅速发展，对信号在频域进行测量和分析的要求也越来越高，传统的频谱分析仪已经显现出一系列的缺点。

With the rapid development of microelectronic , signal processing and computer technologies , the demand for signal measurement and analysis in frequency-domain is increasingly high , so a series of drawbacks showed in traditional analog spectral analyzers .

频域介电测量谱的Kramers-Kronig修正

Kramers - Kronig revision of frequency - domain dielectric measurement

裂变中子（252Cf）对裂变链（235U系统）的依存关系，它是各种频域和时域测量核信息系统反应性的基础。

The dependency relation of fission neutron ( 252Cf ) - fission chain ( 235U system ) is the foundation for reactivity measurement of nuclear information systems in frequency domain and time domain .

频域法自动测量兰姆波的色散特性

Auto-measurement of the dispersive characteristic of lamb waves by frequency domain method

一种超宽带信号的频域分析与测量方法

Frequency Domain Radiated Measurements of Ultra-Wide Band Devices

电介质的频域特性与测量

Measurement and frequency range characteristic of the dielectric

频谱分析仪是对频域信号进行测量和分析的一种重要的测量仪器。

The spectrum analyzer is a very important instrument in measuring and analyzing the signals in frequency domain .

比较了时域近场测量和频域近场测量，得到时域近场测量的优缺点及适用范围。

Then it compares time-domain near-field measurement with frequency-domain near-field measurement with the merits of time-domain near-field measurement given .

按照频域功率定义测量无功功率需要实现电压或电流信号的90°相移。

According to the power definition in frequency-domain , reactive power measurement needs to realize 90 ° phase shift of voltage or current signal .

然后利用频域和时域测量系统，测量了典型隐身目标的电磁散射特性，并与计算结果进行了对比分析。

The electromagnetic scattering characteristics of the representative targets are measured by the systems . And the calculated results and the measured results are analyzed .