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矢网中噪声选件的校准方法研究 总被引:1,自引:0,他引:1
《中国测试》2017,(8):6-10
为解决矢网中噪声选件的计量问题,分析当前该类产品的测量原理,指出现有校准方法无法对矢网中噪声选件开展计量的原因。参照当前矢网的校准方法,提出一种整体校准方案,并报道该方案的基本要求。基于无源器件的噪声稳定特点,提出失配空气线和衰减器作为检验件的新型实现形式。在对比分析现有矢量和标量两种方法无源器件噪声标准值计算方法的基础上,报道检验件标准值包含温度信息的矢量计算方法。通过检验件与低噪声放大器级联的方式,实现矢网中噪声选件的整体校准。该方案分别在Keysight公司和RS公司的产品中进行试验,测量频段6~18 GHz,校准结果的偏差分别为0.4 dB和0.6 dB。 相似文献
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群时延是系统的重要指标之一,而群时延的测量一直是测量领域的难点和热点.本文采用PNA矢量网络分析仪测量微波器件的群时延,并结合实验,给出了测试结果和不确定度. 相似文献
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如何扩大矢量网络分析仪的动态范围 总被引:1,自引:0,他引:1
本文叙述了矢量网络分析仪动态范围的定义及其相关概念,对HP8510C矢量网络分析仪动态范围的方法进行了讨论,并提出了相关建议。 相似文献
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为提高测量RCS值的扫频方法的精度,从环境要求入手,提出了改进环境的基本措施,给出了一些解决的办法;最后通过测试技术手段消除了隔离误差.从结果可以得出测量的精度达到要求. 相似文献
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微波衰减测量在军事计量中具有很重要的意义,关于计量检定人员如何正确选用仪器和元器件以及在操作过程中如何尽可能减小各种误差等问题显得尤为重要。本文在详细介绍微波衰减测量中常用衰减器以及主要测量与校准方法的基础上,结合实际工作经验针对衰减测量与校准中的注意事项进行了探讨。 相似文献
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《IEEE transactions on instrumentation and measurement》1984,33(2):101-105
For automatic precision attenuation measurements, the double phase-modulation technique has been proposed, which employs two kinds of phase modulation instead of the amplitude modulation used in the modulated subcarrier method. The technique is analyzed theoretically and a 10-GHz automatic attenuation measurement system is constructed and tested. 相似文献
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《IEEE transactions on instrumentation and measurement》1968,17(4):308-313
The Hewlett-Packard computer-controlled network analyzer performs fully automatic rapid characterizations of passive and active networks through their scattering parameters. It is extremely flexible in both measurement capability and presentation results, and provides standards laboratory accuracy. System operation is discussed, and in particular, the sources of error involved in making such measurements are dealt with: imperfect standards used for calibration, instrumentation, and signal source accuracy and repeatability errors. Total system accuracies and some measurement results are given. 相似文献
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采用传递比较法对二厘米微波衰减标准装置不确定度进行了验证。测量标准装置的重复性以组内实验标准偏差sn(A)定量表征,测量标准装置的稳定性用组间实验标准偏差sm定量表征。 相似文献
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提出一种基于里德堡原子量子相干效应的功率测量新方法。将装有铷蒸气的低电磁扰动原子气室置于特定的导波系统中,基于里德堡原子量子相干效应将对导波电场测量转化为对原子吸收光谱的探测,利用功率和导波电场的解析量化关系,实现一种全新的可溯源至普朗克常数的微波功率测量。在10.22GHz频率处与传统功率测量进行比较,-40dBm至-20dBm的功率范围内两者平均偏差为0.08dB(1.86%)。这种全新的微波功率量子测量方法具有灵敏度高、动态范围大、测量不确定度小等优势,有望形成新一代可直接溯源至国际单位制(SI)的微波功率基准。 相似文献
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《IEEE transactions on instrumentation and measurement》1978,27(1):33-38
This paper describes an accurate microwave attenuation and phase-shift measurement method using stepped phase modulation. The optimum number of steps is analyzed. Two kinds of measurement system are proposed in consideration of the analysis results. One is suitable for simultaneous and automated accurate measurement of attenuation and phase shift. The other fits attenuation measurement with a wide dynamic range. 相似文献
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《IEEE transactions on instrumentation and measurement》1969,18(3):225-231
The excellent relative frequency stability of the output of two microwave oscillators phase-locked to a common reference signal permits the use of an audio intermediate frequency in the superheterodyne measurement of microwave attenuation. The phase-lock feature also permits the measurement of microwave phase at the audio frequency. The choice of the audio instead of the more conventional 30-MHz intermediate frequency is made on the basis of the low cost and convenient operation, for similar accuracy, of an audio ratio transformer and audio phase shifter in comparison with a 30-MHz cutoff attenuator and 30-MHz phase shifter. A measurement system of this type has been operated at frequencies ranging from 2.5 to 18 GHz. The basic reference signal for phase lock is fed into harmonic mixers associated with the signal source and local oscillator. The outputs of the harmonic mixers go to phase discriminators that control the microwave oscillator frequencies. The precision of measurement at a signal frequency of 10 GHz varies from ±0.0002 dB for an attenuation step of 10 dB or less, to ±0.001 dB for a 50-dB step. 相似文献
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《IEEE transactions on instrumentation and measurement》1969,18(4):283-289
A system is described for the measurement of the magnitude and phase of the reflection coefficient over wide frequency bands. The method consists of recording the voltage at several points along the standing-wave pattern in a coaxial line. A fixed probe is used and the distance between the probe and the load is altered by successively inserting several lengths of precision coaxial line. Knowing these lengths and the frequency of the signal, a curve representing the standing-wave pattern is fitted to the experimental points by means of a computer program performing a least-squares minimization. To cover a given frequency band, the frequency is changed in discrete steps and the corresponding probe voltage recorded automatically. The measured impedance is referred directly to the characteristic impedance of air-dielectric coaxial lines. 相似文献