Method and a test setup for measuring large-signal S-parameters

• US 20040257092A1
• Filed: 06/01/2004
• Published: 12/23/2004
• Est. Priority Date: 06/11/2003
• Status: Active Grant

• Current Assignee: Keysight Technologies, Inc.
• Original Assignee: Jan Verspecht
• Inventors: Verspecht, Jan
• Granted Patent: US 7,038,468 B2
• Time in Patent Office: Days
• US Class Current: 324/638
• CPC Class Codes: G01R 27/28 Measuring attenuation, gain, phase shift or derived characteristics of electric four pole networks, i.e. two-port networks; Measuring transient response in line transmission systems H04B3/46

Abstract

The values of the parameters of a large-signal S-parameter model of a device-under-test are determined by using a frequency-offset probe-tone method and by measuring and processing the spectral components of the scattered voltage waves with frequencies equal to the fundamental frequency, the fundamental frequency plus the said frequency offset and the fundamental frequency minus the said frequency offset.

The resulting large-signal S-parameter model accurately and completely describes the amplifier nonlinear behavior with a large one-tone excitation at the input in a near matched environment at the output.

Claims

1. A method for characterizing a device under test (DUT) comprising the steps of:

providing a first sinusoidal signal having a first frequency to a first signal port of the DUT as a power tone signal

providing a second signal having a second frequency to a second signal port of the DUT as a probe tone signal, whereby the difference between the said second frequency and the said first frequency is equal to a third frequency

determining the spectral components of the traveling voltage waves which are incident to the said DUT signal ports and the traveling voltage waves which are scattered by the said DUT signal ports and this for a frequency equal to the said first frequency, equal to the said second frequency and equal to the said first frequency minus the said third frequency

2. The method of claim 1, whereby the measured values of the said spectral components are being used for calculating the “

large-signal S-parameters”

of the DUT

3. The method of claim 1, whereby the said first signal and the said second signal are provided to the said DUT in a circuit simulator and whereby the said determination of the said spectral components is provided by performing a circuit simulation

4. A method for determining the scattering parameters of a device under test (DUT) comprising the steps of:

providing a first sinusoidal signal having a first frequency to a first signal port of the DUT as a power tone signal

providing a second signal having a second frequency to a second signal port of the DUT as a probe tone signal, whereby the difference between the said second frequency and the said first frequency is equal to a third frequency which is substantially smaller than the said first frequency

measuring the spectral components of the traveling voltage waves which are incident to the said DUT signal ports and the traveling voltage waves which are scattered by the said DUT signal ports and this for a frequency equal to the said first frequency and equal to the said second fre-quency

using the measured values of the said spectral components for calculating the scattering parameters of the said DUT