Limited Sampling Rate

[Paloma-96]

Hardware

• SDR: USRP B210 connected locally

Software

• Operating System: Ubuntu 22.04
• SDR++: v1.1.0

Bug Description Even though the maximum supported sampling rate is higher, the maximum Sample Rate in GUI is 16 MHz, both using USRP and SoapySDR driver.

How can I increase the max sampling rate?

[zekiispa]

Hello , Normally the device promises 56MHZ bandwidth. I have the same problem with the USRP B200mini. I cannot see more than 16mhz bandwidth on the screen.

[AlexandreRouma]

Not a bug, base clock selection just hasn't been implemented yet. I'll change this to a feature request.

[zekiispa]

Got it, thanks.

[AlexandreRouma]

Bandwidth is for the input filter, has nothing to do with available samplerates. As I said in my last response, the reason the samplerate is limited to that value is the baseclock is set to 16MHz. It has to be dynamically adjusted but I have yet to determine an algorithm to select the best options.

[alex0com]

My apologies, previous posts were wrong and I deleted them.

Setting the master clock rate manually allows me to view the full bandwidth using the B210mini clone instead of just 16MHz. What effect this may have beyond just watching the waterfall is beyond my level of understanding.

    // Set the master clock rate to 56 MHz (or adjust as necessary)
    double master_clock_rate = 56e6; // 56 MHz
    dev->set_master_clock_rate(master_clock_rate);
    double actual_clock_rate = dev->get_master_clock_rate();
    if (actual_clock_rate != master_clock_rate) {
        flog::warn("Requested clock rate of 56 MHz, but actual clock rate is {0} MHz", actual_clock_rate / 1e6);
    }

[INFO] [B200] Setting master clock rate selection to 'automatic'.
[INFO] [B200] Asking for clock rate 16.000000 MHz... 
[INFO] [B200] Actually got clock rate 16.000000 MHz.
[16/08/2024 21:50:53.000] [WARN] ConfigManager locked, waiting...
[INFO] [MULTI_USRP] Setting master clock rate selection to 'manual'.
[INFO] [B200] Asking for clock rate 56.000000 MHz... 
[INFO] [B200] Actually got clock rate 56.000000 MHz.

Thanks again for your great work!