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This article presents a standard field generation system with an antenna for the calibration of a Ka-band electric-field probe. We constructed a measurement system having capability of not only rotating the azimuth angle of the probe but also changing the separation distance between the antenna and the probe. As a result, the orientation and separation distance of the probe can be suggested for minimal variation of the measurand, which reduces the overall uncertainty. For traceable electric-field strength measurements, we measured the associated quantities of the power, antenna gain, and impedance of the individual components constituting the field generation system. An evaluation of the uncertainty of the components providing traceability to the system was also conducted. The system is expected to generate a standard field higher than 10 V/m in the frequency range of 26.5–40 GHz. Uncertainty in the correction factors is quantified to determine the factors that affect the calibration, and the expanded uncertainty of the standard field generation system is found to be 5.1% at 26.5 GHz and 5.3% at both 33 and 40 GHz.

To calibrate Ka-band electric field probe standard field generation system with antenna was implemented. For traceability we measured the associated quantities such as power, impedance, and attenuation of each component consisting of the field generation system. Evaluation of uncertainty in components providing traceability to the system was completed. The system is expected to generate standard field more than 30 V/m in the frequency range of 26.5 GHz to 40 GHz.

In this paper, we present calibration and uncertainty evaluation methods for the phase of a radio-frequency comb generator using a calibrated sampling oscilloscope. In addition, we present many solutions that are indispensable for the precise calibration of phase up to 50 GHz. First, we correct the sampling time error, which is the systematic error of the equivalent time sampling system. Second, the frequency response of the oscilloscope is de-convoluted from the measured pulse, and the impedance mismatch between the radio-frequency comb generator and the oscilloscope is calibrated. Finally, we present the calibrated phase of the radio-frequency comb generator and the measurement uncertainty, which demonstrated 95% confidence intervals within ±4.4° up to 50 GHz. The calibrated radio-frequency comb generator, which is traceable to SI units, is used to calibrate a nonlinear vector network analyzer, vector signal analyzer, and oscilloscope. Uncertainties are easily propagated to the measurement uncertainty of other apparatus since it is obtained in the form of covariance.

본 논문에서는 샘플링 오실로스코프의 주파수 응답특성을 측정하는 방법을 제안하였다. 제안된 방법은 샘플링 오실로스코프의 계통오차인 시간축 왜곡 현상과 임피던스 부정합에 의한 영향을 교정할 수 있다. 또한 시간축 에러를 교정한 후에 발생하는 잔여 지터와 기준 펄스 발생 조건에 따라 변하는 scale factor의 정확...

This paper describes in detail how to characterize the response of a commercial real-time digital oscilloscope (RTDO) with traceability. The commercial RTDO usually employs a time interleaving ADC (TIADC) structure. Thus, aliasing is produced when the measurement is separated according to each ADC. As a result, it is difficult to obtain an accurate frequency response for each ADC. In this paper, we propose a method to avoid under-sampling issue, and it can achieve high sampling rate because it is similar to the equivalent sampling method.

This paper describes how to calibrate key parameters (eye amplitude, eye height and eye width) of eye pattern generators using an oscilloscope which is directly traceable to basic physical quantities. Various correction methods are applied to reduce measurement uncertainties, which are estimated by use of the covariance matrix method.

A new calibration method of a power sensor for measuring the peak power of digitally modulated signals is introduced. This method uses an amplitude-modulated sine-wave source and is relatively simple to the currently available method that uses a digitally modulated signal source and an oscilloscope. Basic theory and calibration procedures for measuring the correction factor for peak power are described. Using a commercial peak power sensor that is calibrated with the proposed method, the peak power of a Global System for Mobile Communications at 900 MHz modulated signal is measured and compared with that measured by an oscilloscope. Various examples of choosing the calibration parameters are also discussed. The best uncertainty in the calibration of a peak power sensor is estimated to be 0.34% (k = 2).

In this paper, we introduce a simple and wideband characterization method for electric field probes using a transfer standard. As a transfer standard, a thin disk-type reference probe that can operate from 50 to 1000 MHz is used and calibrated using a micro transverse electromagnetic (mu-TEM) cell. A gigahertz transverse electromagnetic (GTEM) cell is used to generate a reference electric field. It has been shown that the uncertainty of the proposed method can be increased due to the imperfection of the field condition in the cell. According to the measurement result, the proposed characterization method for the electric probes agrees within 6.3%, compared with the method that uses the TEM cell and standard antennas in a fully anechoic chamber.

This paper describes how to calibrate phase response of oscilloscopes, especially at low frequencies from 10 MHz to 1 GHz. The method uses the phase response of a standard mixer calibrated by three-mixer method as the reference phase. We describe basic principles and show results obtained using a balanced mixer and a real-time oscilloscope (1 GHz BW).

A novel method is proposed for the calibration of channel mismatch in a time-interleaved real-time digital oscilloscope (RTDO). A simple simultaneous equation is derived from the Fourier transform of the time-interleaved signals. Thus, it only requires a transfer function of time-interleaved ADCs (TIADCs), while most of previous works have employed additional filters. A measurement method for the transfer function of a commercial RTDO is also proposed. The accuracy of the calibration method is determined by the noise produced after the interleaving process. To validate the proposed method, we measure two-tone signals using a commercial RTDO. The calibrated results clearly show signals at spurious frequencies are substantially reduced.

A practical return loss measurement system that utilizes mature radio-over-fiber technology has been demonstrated. The S 11 of an antenna measured using frequency-multiplied optical links is in good agreement with that obtained using a conventional one.

A new calibration method of a peak power sensor measuring digitally modulated signals is introduced. This method uses an AM modulated sine wave source and is relatively simple to the currently available method which uses a digitally modulated signal source and an oscilloscope.

The nose-to-nose calibration method is applied to find the impulse response of broadband sampling oscilloscope (Tektronix SD-32, 50 GHz bandwidth). The result obtained is compared with the one measured using the swept-sine method and then used to calibrate the impulse response of an oscilloscope with 20 GHz bandwidth.

A calibration system of a 3.5 mm coaxial power sensor was implemented using transfer standards with 7 mm coaxial or K-band waveguide input connectors. A 7 mm-3.5 mm or WR42-3.5 mm adapter was used to form a combined transfer standard. The effective efficiency of the combined transfer standard was obtained. The 3.5 mm coaxial power sensor was calibrated using the well-known direct comparison method and measurement uncertainty was evaluated.