Measure 200MHz 5GNR Signal with PXIe-5832 and RFmx

In 3GPP defined 5G NR, a single RF carrier bandwidth can be from 50MHz and up to 400MHz in frequency range 2. If the users test 5G NR transceiver and to check the RF signal analysis result of the transceiver with NI RFmx (Latest tested version 2023 Q2) and VST (PXIe-5831/5832), he/she will encounter error message Error: PLL could not phase-lock to the external reference clock. Make sure your reference clock is connected and that it is within the jitter and voltage specifications. Also, make sure the reference clock rate is correctly specified - Error code 1074097770. 

This article discusses an alternate method for measuring RF transceiver with RF bandwidth of 200MHz. The intended audiences are NI-RFmx users who have basic knowledge of 3GPP 5G NR specifications, NI-VST and NI-RFmx.  

1. Refer to PXIe-5832 Getting Started Guide to set up the system, and configure PXIe-5832 with NI-MAX as below:

2. Launch RFmx Waveform Creator by typing RFmx Waveform Creator in the Search bar next to Start
3. Set up the waveform in frequency range 2 and the bandwidth of 200MHz, shown below:

4. Set the Center Frequency in FR2, 26.5GHz for example, click on Create & Play, refer to below for the setting and error message:

5. The alternative method is to Configure the associated devices LO1 (mmWave LO) as Not Specified, shown below:

6. After reconfiguring the Associated Devices, the system works for RF bandwidth of 200MHz, both RFmx Waveform Creator and RFmx Soft Front Panel screen shoots shown below: