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 signal adjustment device includes a frequency adjustment circuit, a filter circuit, and a power estimation circuit. The frequency adjustment circuit is configured to receive a two-tone signal from a signal generator and to generate a first signal according to the two-tone signal, wherein the signal generator generates the two-tone signal according to a first coefficient and a second coefficient. The filter circuit is configured to filter the first signal, in order to generate a second signal. The power estimation circuit is configured to detect a power of an intermodulation distortion from the third order signal component, which is associated with the two-tone signal, in the second signal, and to adjust at least one of the first coefficient and the second coefficient according to the power, in order to reduce the power.

The invention relates to a method for determining a deviation of a broadband measurement signal from a reference signal. The method provides the steps: subdivision of the signal into at least two measurement-signal frequency bands; displacement of the measurement-signal frequency bands; and reconstruction of the at least two measurement-signal frequency bands. A corresponding measurement device is also contained within the idea of the invention.

The invention relates to a method for determining a deviation of a broadband measurement signal from a reference signal. The method provides the steps: subdivision of the signal into at least two measurement-signal frequency bands; displacement of the measurement-signal frequency bands; and reconstruction of the at least two measurement-signal frequency bands. A corresponding measurement device is also contained within the idea of the invention.

A system and method for determining the linearity of a device-under-test combine a first periodic signal and a second periodic signal to produce a combined signal, wherein the second periodic signal has at least one of a phase difference and a frequency difference with respect to the first periodic signal, and applying the combined signal to an input of the device-under-test. The linearity of the device-under-test is determined from an output signal of the device-under-test based on the at least one of the phase difference and frequency difference between the first periodic signal and the second periodic signal.

A system and method for determining the linearity of a device-under-test combine a first periodic signal and a second periodic signal to produce a combined signal, wherein the second periodic signal has at least one of a phase difference and a frequency difference with respect to the first periodic signal, and applying the combined signal to an input of the device-under-test. The linearity of the device-under-test is determined from an output signal of the device-under-test based on the at least one of the phase difference and frequency difference between the first periodic signal and the second periodic signal.

Provided is a method for testing a semiconductor device having an A/D converter, the method includes supplying a sinusoidal analog test signal S1 to an A/D converter, storing a group S2 of output codes generated by the A/D converter over a period with an integer K multiple duration of the cycle of the sine wave, in response to the analog test signal S1, and generating a histogram of the stored group S2 of the output codes, and evaluating the A/D converter on the basis of the histogram.

A testing method or apparatus utilizes a filter or modifier to measure time varying or dynamic harmonic, intermodulation, cross modulation, and or N-Beat or triple distortion from a device. With a stairstep or arbitrary signal and another signal, Nth order harmonic, cross modulation, triple beat, N-Beat, and or intermodulation distortion is measured via the filter or modifier at different offsets or time provided by an arbitrary low frequency signal. For example, an amplifier with crossover distortion will show increased (e.g., time varying) harmonic, cross modulation, triple beat, and or intermodulation distortion near the zero crossing while providing less distortion in other portions of the transfer curve of the amplifier. One or more distortion signals from the device (e.g., audio device) may be measured for a phase and or frequency modulation effect.

A testing method or apparatus utilizes a filter or modifier to measure time varying or dynamic harmonic, intermodulation, cross modulation, and or N-Beat or triple distortion from a device. With a stairstep or arbitrary signal and another signal, Nth order harmonic, cross modulation, triple beat, N-Beat, and or intermodulation distortion is measured via the filter or modifier at different offsets or time provided by an arbitrary low frequency signal. For example, an amplifier with crossover distortion will show increased (e.g., time varying) harmonic, cross modulation, triple beat, and or intermodulation distortion near the zero crossing while providing less distortion in other portions of the transfer curve of the amplifier. One or more distortion signals from the device (e.g., audio device) may be measured for a phase and or frequency modulation effect.

According to methods of performing a passive inter-modulation distortion (“PID”) test, a first excitation signal and a second excitation signal are applied to a device under test, where at least one of the first and second excitation signals is a spread spectrum excitation signal. An output signal is received that includes a PID signal generated from mixing of the first and second excitation signals. At least a portion of the output signal is de-spread. A characteristic of the PID signal may then be measured.