Digi Regulatory Firmware (F1416): modulated transmit vs u-blox non-signaling transmit

I am using Digi dev board XBIB-CU-TH, the modem is XBee3 LTE-M/NB-IoT, which has been loaded with the Digi Regulatory Firmware F1416. The firmware works pretty well with the Bluetooth DTM testing. The cellular testing, on the other hand, has been very troublesome in the Transparent Mode. I then switch to the USB Direct Mode, so I can use the u-blox m-center software to conduct the test by directly interacting with the SARA R410M module.

My question is - The Regulatory Firmware offers a “modulated transmit” test with a specific UL EARFCN and power settings. The u-blox has something called “non-signaling mode” transmit test with a specific EARFCN and power level as well. Are these two functions the same? I know the observations from my spectrum analyzer are different. Using u-blox m-center, I can issue a non-signaling transmit on channel, for example, 19950 (band 4), and get a nice frequency distribution centered at 1710 MHz. The “modulated transmit”, same channel and power, I couldn’t see anything on the spectrum analyzer.

In case you ask - No, I don’t have a callbox.

Acpie360 We are aware that there is issues with the current Regulatory code. There will be an updated version released sometime in the near future that will have this resolved. I believe that may be what you are observing.

mvut - Thanks for the comment. Would you be able to tell me if the Regulatory Testing Command AT%5 is equivalent to the u-blox AT+UTEST=3, assuming EARFCN and power level are the same? The Digi UG describes AT%5 as “start modulated transmit”, while the u-blox describes AT+UTEST=3 as non-signaling transmit. I just want to know what the differences are.

Can you please provide the U-Blox manual you are referring to?

Here is the AT command link:

Section 19.8.5 (page 494) - TX mode setting (=3)


The radio module that is inside of the XBee 3 NBiOT module you have is the SARA-R410. That manual you are referencing is not included in it.

I am so sorry - I copied from Google search without checking. Here is the one:

Page 186 TX mode setting (=3)

I guess what I am really asking is - What is the equivalent u-blox AT command for the Digi Regulatory Firmware command AT%5?

I confirmed that the AT%5 command along with the others for setting the channel, power level Etc. is equal to the +UTEST=3 command and its associated functions.

Thanks you!
This means what u-blox refers as “non-signaling transmit” is the same as what Digi refers as “modulated transmit”, correct? I’d think probably Digi should call it as “unmodulated” transmit.

If that is how you feel, then I would suggest using the Feedback function in the manual and suggest that.