05 | Keysight | Measurement Applications for the E6640A EXM Wireless Test Set - Solution Brochure

EVM

Power

Power

Power

Power

Power

EVM, power

EVM, power,

spectral mask

Sequence

Second acquisition

First acquisition

Measurement steps

Acquisition 1

Acquisition 2

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

Step 1

Step 2

Step 3

Figure 3. An example of the EXM’s WLAN sequencer

An EXM sequence can be comprised of up to hundreds of separate acquisitions and

in each case the frequency, expected signal level, and trigger conditions can be

programmed. Figure 3 shows two such acquisitions. Within each acquisition, a number

of measurement steps can be defined that will normally be programmed to match the

programmed output from the DUT using its sequence mode. Each measurement step

can be set up to process and return one or more measurement results from the data

acquired in that time period. In the figure, there are six measurements made on the data

from the first acquisition. The EXM sequence is constructed to match the sequence

programmed in the DUT, and when initiated, both are executed together.

Smart Scheduling Instrument

Another test technique supported by EXM is the use of an intermediate test scheduling

executive to manage the TRX to ensure maximum use of the test resources and ensure

maximum production throughput.

Keysight’s name for this is Smart Scheduling Instrument (SSI) and it allows an interme-

diate test scheduling program to manage instrument control and test execution in a way

that allows each DUT to see a “virtual VSA/VSG” independent of the number of physical

TRXs populated in the EXM.

This approach to dynamic resource allocation can improve test efficiency significantly.