Problem with generating high frequency(100Mhz) signal using USRP X310 and Labview

[Lee9808]

Hi everyone

Im now struggling with generating a high frequency(about 100Mhz) sinusoidal signal using USRP X310.

To make a 100Mhz sinusoidal signal, it looks like i have to set I/Q rate about upper 200M.

But there're some error code(Underflow, lowering I/Q rate).

I couldn't know what can i do for performing labview with high I/Q rate.

Here is a picture about my labview code.

Regards,

Lee

[ni_hj · Accepted solution]

Hi,

Please clarify it. what do you mean by "100Mhz sinusoidal signal"?

sinusoid signal as a tone signal does not have bandwidth, zero bandwidth.

What is that 100MHz, is it carrier/center frequency or bandwidth of your baseband signal?

- If it is your carrier frequency, only set "carrier frequency" to 100MHz (X310 support RF frequency from DC to 6GHz), and then you need to select your baseband frequency and sampling rate that is way less than 100MHz. (you do not need to set your sampling rate to 200Msps for this case!)

- if 100MHz is your baseband signal bandwidth, you need to select carrier frequency higher.

BTW, USRP X310 can support instantanously160MHz with 200Msps. But in practice you can approach less than that. Furthermore, you need to consider several limitation in your hardware setup, software, and configuration setup. and need to modify several setting.

what physical connection you use to upload IQ samples to your laptop from USRP.

[Lee9808]

Im sorry not to clarify the meaning of "100Mhz sinusoidal signal".

It means i want to make baseband signal's frequency as 100Mhz.
If you look at my code, my code's Coarsed IQ rate is connected to Baseband's Sampling Rate.
So when i set the signal frequency as 100Mhz, it looks like i have to set IQ rate around 200Mhz.
But because of my laptop performance, IQ rate has a limit about 25Ms/s.
Im now using 1Gigabit Ethernet to communicate with labtop and USRP X310, so Im going to change it 10Gigabit ethernet.

But I'm not sure what I'm working on will work.