Optoelectronic time-domain characterization of a 100 GHz sampling oscilloscope

Abstract

We have performed an optoelectronic measurement of the impulse response of an ultrafast sampling oscilloscope with a nominal bandwidth of 100 GHz within a time window of approximately 100 ps. Our experimental technique also considers frequency components above the cutoff frequency of higher-order modes of the 1.0 mm coaxial line, which is shown to be important for the specification of the impulse response of ultrafast sampling oscilloscopes. Additionally, we have measured the reflection coefficient of the sampling head induced by the mismatch of the sampling circuit and the coaxial connector which is larger than 0.5 for certain frequencies. The uncertainty analysis has been done using the Monte Carlo method of Supplement 1 to the 'Guide to the Expression of Uncertainty in Measurement' and correlations in the estimated impulse response have been determined. Our measurements extend previous work which deals with the characterization of 70 GHz oscilloscopes and the measurement of 100 GHz oscilloscopes up to the cutoff frequency of higher-order modes.

Metrology State-of-the-Art and Challenges in Broadband Phase-Sensitive Terahertz Measurements

“…As the pulse response shows a gradual degradation the result is less prone to truncation artifacts [82]. These approaches also show strong links to developments made with THz VNAs [83].…”

“…Error-correction and uncertainties in EOS have received considerable attention within the NMI community [82,83], because the waveform needs to be evaluated at the plane of the DUT, rather than simply measured at a point on the coplanar waveguide substrate. For example, in a VNA, the forward and reverse travelling electrical waves are often separated using directional-couplers in the test-set, but in an EOS both components contribute to the measured temporal field.…”

“…For example, in a VNA, the forward and reverse travelling electrical waves are often separated using directional-couplers in the test-set, but in an EOS both components contribute to the measured temporal field. Workers at PTB in Germany [83] have measured the field at two points on the transmission line, making it possible to separate the forward and reverse waveforms. This work demonstrated that corrections can be applied successfully to determine the impedance-match corrected response of the instrument.…”

The problem of calibrating Laser-Doppler Vibrometers at high frequencies

“…The experimental setup and characteristic features of the femtosecond laser are shown in figure 8. Among many other applications such femtosecond lasers are routinely employed for the characterization of the time response of 70-GHz and 100-GHz sampling oscilloscopes [15,16].…”

Method for Measuring the Phase Spectrum of the Output of a Frequency Source Used in the Calibration of an Electroshock Weapon Characterization System

“…The phase spectral output is obtained using mathematical operations on the magnitude spectrum that are valid if the instrument exhibits certain idealized behavior [3]. There are other techniques for calibrating waveform recorders, but these are usually directed at high-bandwidth equivalent-time sampling instruments and are not applicable or appropriate for the ESW measurement system, which uses real-time single-shot waveform recorders [4][5][6][7]. Even for these high-bandwidth techniques, swept-frequency methods are used as the reference for their magnitude response.…”