A high-frequency 5 measurement method includes generating a test signal (TS), which is a sine-wave signal having a predetermined frequency, in which a period (τ) during which the power level is at a first power level and a period (T-τ) during which the power level is at a second power level lower than the first power level 10 are periodically repeated, inputting the test signal (TS) to a device under test (10) as an input signal, and measuring the difference between an output signal (OUT) of the device under test (10) and an ideal value of the output signal (OUT).

A method for instantaneous load pull impedance pattern generation uses a phase-frequency-location equivalent of the natural behavior of slide screw tuners to skew the reflection factor phase with only small frequency changes. The method is generic and applies the same to all GHz range test frequencies. A simple calculation determines the tuning probe position and the impedance cloud is generated quasi instantaneously by switching between sidebands of the carrier test frequency without mechanically moving the tuning probe. Benign frequency behavior of the tuners allows for simple and accurate narrowband interpolation. Duration of load pull measurements is reduced from minutes to seconds.

A method for examining differential pair transmission lines, performed by a processor, comprising: capturing a plurality of first insertion losses of a first signal line within a frequency range and a plurality of second insertion losses of a second signal line within the frequency range, wherein the first signal line and the second signal line are configured to transmit a pair of differential signals; calculating a plurality of maximum error ratios between the first insertion losses and the second insertion losses within the frequency range; determining whether any one of the maximum error ratios is greater than or equal to an upper threshold; outputting a warning signal when the processor determines one of the maximum error ratios is greater than or equal to the upper threshold; and ending the method when the processor determines each one of the maximum error ratios is smaller than the upper threshold.

A method for examining differential pair transmission lines, performed by a processor, comprising: capturing a plurality of first insertion losses of a first signal line within a frequency range and a plurality of second insertion losses of a second signal line within the frequency range, wherein the first signal line and the second signal line are configured to transmit a pair of differential signals; calculating a plurality of maximum error ratios between the first insertion losses and the second insertion losses within the frequency range; determining whether any one of the maximum error ratios is greater than or equal to an upper threshold; outputting a warning signal when the processor determines one of the maximum error ratios is greater than or equal to the upper threshold; and ending the method when the processor determines each one of the maximum error ratios is smaller than the upper threshold.

A vector network analyzer is provided which includes a first measuring port, a digital interface connected to the first measuring port, a second measuring port adapted to be connected to a radio frequency (RF) input or output of a device under test (DUT), and a processor. The digital interface is adapted to be connected to a digital input or output of the DUT. The processor is adapted to determine scattering parameters (S-parameters) of the DUT based on measuring signals transmitted to the DUT and received from the DUT by the first measuring port and the second measuring port.

A vector network analyzer is provided which includes a first measuring port, a digital interface connected to the first measuring port, a second measuring port adapted to be connected to a radio frequency (RF) input or output of a device under test (DUT), and a processor. The digital interface is adapted to be connected to a digital input or output of the DUT. The processor is adapted to determine scattering parameters (S-parameters) of the DUT based on measuring signals transmitted to the DUT and received from the DUT by the first measuring port and the second measuring port.

The present invention provides a radio field intensity measurement device having a display portion with improved visibility, in the case of measuring a weak radiowave from a long distance. In the radio field intensity measurement device, a battery is provided as a power source for power supply and the battery is charged by a received radiowave. When a potential of a signal obtained from the received radiowave is higher than an output potential of the battery, the power is stored in the battery. On the other hand, when the potential of the signal obtained from the received radiowave is lower than the output potential of the battery, power produced by the battery is used as power to drive the radio field intensity measurement device. As an element to display the radio field intensity, a thermochromic element or an electrochromic element is used.

The present invention provides a radio field intensity measurement device having a display portion with improved visibility, in the case of measuring a weak radiowave from a long distance. In the radio field intensity measurement device, a battery is provided as a power source for power supply and the battery is charged by a received radiowave. When a potential of a signal obtained from the received radiowave is higher than an output potential of the battery, the power is stored in the battery. On the other hand, when the potential of the signal obtained from the received radiowave is lower than the output potential of the battery, power produced by the battery is used as power to drive the radio field intensity measurement device. As an element to display the radio field intensity, a thermochromic element or an electrochromic element is used.

A method for measuring (and controlling) a characteristic performance parameter Γ.sub.s of a device under test (DUT) having an input port (at the minimum). The method involves connecting the input port of the DUT to a signal generator, subjecting the DUT to a large signal input test signal, and executing a first measurement of the incident wave and reflected wave at a DUT input reference plane. The method further involves subjecting the DUT to a perturbation signal combined with the large signal input test signal, and executing a second measurement of the incident wave and reflected wave at the DUT input reference plane, and determining the characteristic performance parameter from the first measurement and the second measurement.

The present disclosure relates to a method for testing a device under test by using a test system. The method comprises the steps of: generating a wideband modulated signal; forwarding the wideband modulated signal to an input of a device under test; separating an electromagnetic wave reflected at the input by the directional element; forwarding the reflected electromagnetic wave to a test and measurement instrument; processing a reference signal associated with the wideband modulated signal; and determining a channel response by taking the reference signal and at least one scattering parameter of the device under test into account, wherein the scattering parameter depends on the reflected electromagnetic wave. Further, the present disclosure relates to a test system.