EMC certification, 52840 DTM working with the R&S CMW 500

[Dave M]

Working with Jay Tyzzer ([email protected]) out of southern California.  We're having our units tested for EMC certification and the test house has requested a DTM loaded unit that would work with the R&S CMW 500 however we do not have a two wire interface, just the USB integrated with the 840. Is there a setting configuration on the CMW 500 that will allow this to work?  Could the test house not simply use the FCC standard test load which permits any modulation scheme, power level and frequency to be set?

Using a 52840 with USB to go through certification. We have implemented the standard FCC load which permits setting power level, frequency, modulation, duty cycle etc. which works fine. Our test house (SGS Atlanta USA) is wanting to connect with their Rohde & Schwarz CMW 500 test set. We do not have pins available to support a two wire interface so we've tried to code the unit to use the USB instead. This is being problematic as the CMW 500 standard configuration requires the two wire interface. 

Is there a way to configure the CMW to use the 840 native USB?

Cannot the same tests be done using the FCC load?

 What would your recommendation be?

[run_ar]

Hi,

Unfortunately we are using an Anritsu tester for DTM inhouse, so not sure what is supported by the R&S CMW500. Regardless our DTM solution is a standard UART implementation. As you say it is possible to change this to control the unit over USB, but that requires some kind of manual test mode on the tester, i.e. a mode that lets you control the DUT manually.

Unfortunately the RF-PHY test requires DTM and cannot be performed using the standard radio test example.

[Dave M]

As it turns out we were able to get our test house to push the required driver to the CMW500 so they could indeed use the USB connection. We used the utility Zadig 2.2-XP and installed the “USB Serial (CDC)” driver.  (https://zadig.akeo.ie/) That worked for them.