Patent ID: 11933848
Assignee: NATIONAL INSTRUMENTS IRELAND RESOURCES LIMITED
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 11:
12. A method for determining at least one characteristic of a device under test, DUT, at a given frequency, the method comprising:
a) generating a first periodic modulated signal across the frequency range
b) generating a second periodic modulated signal with a frequency offset from the frequency range;
c) performing a measurement, at one or more ports of a plurality of ports of the DUT while the first periodic modulated signal is applied to a first port of the DUT and the second periodic modulated signal is applied to a second port of the DUT, of one or more
voltages and currents, or
incident and reflected waves,

wherein performing the measurement comprises:
obtaining probed signals by probing one or more of
the voltages and currents, or
the incident and reflected waves,

receiving probed signals in a multi-channel receiver structure comprising a plurality of receivers and digitizer, by switching between a plurality of probed signals from one of multiple signal probing hardware circuits, wherein the digitizer digitizes the received probed signals and has its own sample clock derived from a master clock,
performing a signal reconstruction to identify in a phase-coherent way the individual digitized probed signals, and
processing the phase coherently digitized probed signals to obtain one or more of
the measured voltages and currents, or
incident and reflected waves,

d) determining the at least one characteristic as a function of time across the frequency range, using one or more of
the measured voltages and currents,
or incident and reflected waves.