S-parameters are widely used to detail the scattering parameters of radio frequency (RF) components and microwave circuit modules. The vector network analyzer (VNA) is the most commonly used device for measuring S-parameters. Given the multiple frequency points, complex values, and intricate uncertainty propagation involved, accurately assessing the uncertainty of S-parameter measurements is difficult. In this study, we proposed a new method for assessing S-parameter uncertainty based on the covariance matrices, tracing back to the nominal uncertainty of calibration standards. First, we analyzed the relevant theory of uncertainty assessment using covariance matrices and subsequently deduced the mechanism of Type B uncertainty propagating from calibration standards to error model coefficients and S-parameter measurements to evaluate Type B measurement uncertainty. In this study, a novel measurement system was constructed for measuring grounded coplanar waveguides by using a VNA and calibration standards with 8- and 12-error models. Initially, the model assessed the Type B uncertainty of measuring four S-parameters of a grounded coplanar waveguide. Next, the VNA calibrated with the 12-error model was used to conduct multiple repeated measurements to assess the Type A uncertainty of the grounded coplanar waveguide. Finally, the composite uncertainty was constructed, which demonstrated that the proposed method can be used for assessing the uncertainty of S-parameters.

The bandwidth of a broadband sampling oscilloscope is a crucial performance indicator, as a result of which expanding its measurement bandwidth without altering the oscilloscope hardware has attracted considerable research attention. This study extended the oscilloscope bandwidth by compensating the oscilloscope’s frequency response. First, the theoretical relationship between the oscilloscope’s bandwidth, rise time, and their interdependencies were analyzed. Next, a scheme was designed to acquire the oscilloscope’s frequency response and compensate it in the distortion-free transmission direction. Experimental validation conducted using the Agilent 86100C oscilloscope with the 86117A sampling module demonstrated that the bandwidth extended by 15.2 GHz after frequency response compensation, and the rise time reduced by 2.5 ps. These results confirmed the effectiveness of the proposed approach. Finally, the oscilloscope’s frequency response was compared with varying degrees of compensation and the effect of this modification on the measurement of the same signal was investigated, concluded that there is a better effect when approaching complete compensation.

This study proposes a method to quantify uncertainty in the scattering parameter (S-parameter) measurements when using de-embedding techniques. After calibrating the measurement setup with reference standards, de-embedding algorithms are employed to extract the intrinsic S-parameter of the device under test (DUT). This process introduces additional complexity to the uncertainty analysis. This study investigates the sources of uncertainty inherent to vector network analyzer (VNA) measurements. Subsequently, a covariance matrix-based approach is employed to propagate these uncertainties, culminating in the quantification of S-parameter uncertainty. The effectiveness of the proposed is determined by comparing the measured S-parameters of power dividers and couplers to their nominal values, considering parameters such as balance, coupling, and voltage standing wave ratio (VSWR). Additionally, an uncertainty analysis is conducted for the power divider’s S-parameters, tracing the uncertainty sources back to the calibration standards.

The jitter measurement floor of a broadband sampling oscilloscope represents an effective lower bound for time-domain jitter measurements and can limit the accuracy of low-jitter characterization. Because characterization procedures can be complex and the results are affected by multiple coupled test conditions, this paper develops a systematic time-domain framework for characterizing the jitter measurement floor. A reproducible measurement setup based on a low-jitter signal source is established, and the effects of vertical sensitivity, input frequency, and input amplitude on the jitter measurement floor are quantitatively evaluated. Based on these results, a rapid parameter-sweep and screening procedure is presented to quickly determine the parameter setting range associated with a near-minimum jitter measurement floor. To reduce reliance on ultra-low-jitter reference sources, simulations and experiments are conducted to examine the relationship among the measured jitter, the source jitter, and the jitter measurement floor of the oscilloscope; the results are consistent with a root-mean-square combination model. Leveraging this model, a root-mean-square-based method is introduced to extract the jitter measurement floor, which remains applicable when an ultra-low-jitter source is unavailable. Experimental results support the effectiveness and practical feasibility of the proposed workflow, suggesting an accessible route toward reproducible time-domain characterization of the jitter measurement floor of sampling oscilloscopes.