07 | Keysight | N5465A InfiniiSim Waveform Transformation Toolset for Infiniium Oscilloscopes - Data Sheet

Measurement and simulation circuits

The core of the InfiniiSim waveform transformation software

is in defining two circuits: one that defines your measurement

setup and the other to define what you desire to have as your

measurement. The first we call the ‘measurement circuit’ and

the second is the ‘simulation circuit’. These can be as simple as

one block between the source and the oscilloscope load, or as

complex as nine circuit blocks as in general purpose model. The

simulation and measurement circuits share the topology selected,

however, in many cases, circuit definitions for each block will be

very different from measurement to simulation. This leads to great

flexibility in transforming acquisitions at a measurement point to

any other virtually probed location. For the circuit shown in Figure

6, for instance, Block `P’ has an S parameter file describing its

loading during measurement, however, for simulation, the loading

is desired to be eliminated, thus the `open’ designation.

See what you deserve to see

With the InfiniiSim waveform transformation toolset, you can see

transformed signals in confidence whether channel elements are

being inserted removed or whether the measurement plane is

being relocated. Figure 7 shows a waveform of a digital signal at

1.8 Gb/s going through a combination of fixture and cable. Note

that for the longer sequences of identical digits the waveform

reaches a level that is very different from when the data changes

frequently. This is called ISI and is seen when the channel exhibits

low pass filter characteristics. The fixture and cables were

measured with a 4-port Vector Network Analyzer and removed

using the channel element removal selection in InfiniiSim. The

yellow CH1 trace in Figure 7 depicts the results. Note the blue

waveform depicting the ‘before measurement’ directly at the

transmitter versus the yellow waveform transformed using the

4-port channel model of the fixture.

Figure 7. De-embedded, yellow, channel 1 waveform along with original

channel 3 waveform.

Figure 6. Measurement and Simulation circuits. Blue designates the

measurement circuit elements while the brown labeling designates the

simulation circuit elements.

Model your System as Detailed as you Need (Continued)