A method and a measurement system for determining the noise power of a device under test especially the exact noise power is provided. The measurement method comprises determining a sideband gain of a measurement system using a calibration unit, connecting a device under test to the measurement system, measuring a noise power of the device under test with a receiver and correcting the measured noise power with the determined system gain including a sideband gain.

A method and a measurement system for determining the noise power of a device under test especially the exact noise power is provided. The measurement method comprises determining a sideband gain of a measurement system using a calibration unit, connecting a device under test to the measurement system, measuring a noise power of the device under test with a receiver and correcting the measured noise power with the determined system gain including a sideband gain.

A method of evaluating microwave characteristics includes the steps of: (A) measuring thermal diffusion features and microwave characteristics of at least three mode samples to obtain at least three data points, wherein the mode samples include identical constituents but at different ratios thereof; (B) obtaining a mathematical relation between the data points by linear regression; (C) measuring a thermal diffusion feature of a sample under test, wherein the sample under test and the mode samples include identical constituents; and (D) substituting the thermal diffusion feature of the sample under test into the mathematical relation to evaluate a microwave characteristic of the sample under test. The method is applicable to a ceramic material to evaluate microwave characteristics of the ceramic material.

A method of evaluating microwave characteristics includes the steps of: (A) measuring thermal diffusion features and microwave characteristics of at least three mode samples to obtain at least three data points, wherein the mode samples include identical constituents but at different ratios thereof; (B) obtaining a mathematical relation between the data points by linear regression; (C) measuring a thermal diffusion feature of a sample under test, wherein the sample under test and the mode samples include identical constituents; and (D) substituting the thermal diffusion feature of the sample under test into the mathematical relation to evaluate a microwave characteristic of the sample under test. The method is applicable to a ceramic material to evaluate microwave characteristics of the ceramic material.

A low-profile impedance tuner uses a cam-driven piston-like vertical movement of a metallic tuning probe inside a low loss slabline, controlled by an eccentrically centered disc (cam), which is attached to the axis of a stepper motor and rotates parallel to the slabline walls. The structure combines the benefits of low profile rotating tuning probe control with the benign reflection factor phase trajectory of block tuning probes; this is critical for accurate interpolation and impedance synthesis (tuning) strategies using a limited number of calibration points, especially at high microwave and millimeter-wave frequencies.

A low-profile impedance tuner uses a cam-driven piston-like vertical movement of a metallic tuning probe inside a low loss slabline, controlled by an eccentrically centered disc (cam), which is attached to the axis of a stepper motor and rotates parallel to the slabline walls. The structure combines the benefits of low profile rotating tuning probe control with the benign reflection factor phase trajectory of block tuning probes; this is critical for accurate interpolation and impedance synthesis (tuning) strategies using a limited number of calibration points, especially at high microwave and millimeter-wave frequencies.

Various aspects of the disclosure relate to evaluating the electromagnetic impedance characteristics of a material under test (MUT) over a range of frequencies. In particular aspects, a system includes: an electrically non-conducting container sized to hold the MUT, the electrically non-conducting container having a first opening at a first end thereof and a second opening at a second, opposite end thereof; a transmitting electrode assembly at the first end of the electrically non-conducting container, the transmitting electrode assembly having a transmitting electrode with a transmitting surface; and a receiving electrode assembly at the second end of the electrically non-conducting container, the receiving electrode assembly having a receiving electrode with a receiving surface, wherein the receiving electrode is approximately parallel with the transmitting electrode, and wherein the transmitting surface of the transmitting electrode is larger than the receiving surface of the receiving electrode.

Examples are disclosed for characterizing a transmission line. Sets of scatter parameters (s-parameters) associated with measured or modeled insertion loss (IL) or return loss (RL) values over a range of frequencies may be acquired for a transmission line. One or more parameter values for use in IL or RL fit functions may be adjusted to reach a threshold for a coefficient of determination (R.sup.2) value of a curve generated using the IL or RL fit functions to approximate the set of s-parameters over the range of frequencies. The IL or RL fit functions may then be used to generate other sets of s-parameters associated with IL or RL values for a recreated model of the transmission line. The other sets of s-parameters may be scaled to characterize transmission lines of various lengths. Other examples are described and claimed.

Examples are disclosed for characterizing a transmission line. Sets of scatter parameters (s-parameters) associated with measured or modeled insertion loss (IL) or return loss (RL) values over a range of frequencies may be acquired for a transmission line. One or more parameter values for use in IL or RL fit functions may be adjusted to reach a threshold for a coefficient of determination (R.sup.2) value of a curve generated using the IL or RL fit functions to approximate the set of s-parameters over the range of frequencies. The IL or RL fit functions may then be used to generate other sets of s-parameters associated with IL or RL values for a recreated model of the transmission line. The other sets of s-parameters may be scaled to characterize transmission lines of various lengths. Other examples are described and claimed.

Various implementations include systems and approaches for measuring an electromagnetic impedance characteristic of a fluid under test (FUT) in a fluid channel. In some cases, a system includes: a transmitting electrode assembly including: a transmitting electrode having a transmitting surface; and a transmitting electrode backer ground plate at least partially surrounding the transmitting electrode; a receiving electrode assembly including: a receiving electrode having a receiving surface; and a receiving electrode backer ground plate at least partially surrounding the receiving electrode, where the transmitting electrode and the receiving electrode are located in a set of walls defining the fluid channel, the transmitting surface and the receiving surface each conform to a shape of the set of walls defining the fluid channel, where the fluid channel permits transverse flow of the FUT relative to both the transmitting electrode and the receiving electrode.