comm.SDRuTransmitter can not work with my USRP X310

I use matlab 2025a and I can connect to my USRP X310 in the radioSetupWizard. Actually, I can use basebandtransmitter to control my X310. However, when I use comm.SDRuTransmitter or comm.SDRuReceiver, it reports error as blow.

How can I solve this problem?

Thanks

Configure SDRu Transmitter and Transmit Data

Create an SDRu transmitter System object for your USRP radio at the default IP address, 192.168.10.2. Configure a sample rate of 1 MHz.

mcr = 200e6;
sampleRate  = 1e6;
tx = comm.SDRuTransmitter(Platform="X310", ...
    IPAddress="192.168.40.2",...
    MasterClockRate=mcr, ...
    InterpolationFactor=mcr/sampleRate)

tx =

comm.SDRuTransmitter - :

Platform: 'X310'

IPAddress: '192.168.40.2'

ChannelMapping: 1

CenterFrequency: 2.4500e+09

LocalOscillatorOffset: 0

Gain: 8

PPSSource: 'Internal'

EnableTimeTrigger: false

ClockSource: 'Internal'

MasterClockRate: 200000000

InterpolationFactor: 200

TransportDataType: 'int16'

EnableBurstMode: false

Create a 40 kHz sine wave for transmission.

freq = 40e3;
samplesPerFrame = 50e3;
sinewave = dsp.SineWave( ...
    Amplitude=2,Frequency=freq, ...
    SampleRate=sampleRate, ...
    SamplesPerFrame=samplesPerFrame, ...
    OutputDataType="double", ...
    ComplexOutput=true);
data = sinewave();

Since the input to the SDRu transmitter System object must be in the range [-1,1], normalize the data before transmission.

amp = max(abs(data));
NormalizedData = data/amp;

Create a spectrum analyzer and time scope object to visualize the signal.

spectrumScope = spectrumAnalyzer("SampleRate",sampleRate);
frameDuration = samplesPerFrame/sampleRate;
timeScope = timescope("TimeSpan",4/freq,"SampleRate",sampleRate);
disp("Transmission started");
Transmission started
spectrumScope(NormalizedData);

timeScope(NormalizedData);

Transmit the normalized data for 10 seconds using the SDRu transmitter System object tx.

stopTime = 10;
time = 0;
while time < stopTime
    tx(NormalizedData);
    time = time+frameDuration;
end

Win32; Microsoft Visual C++ version 1936; Boost_108100; UHD_4.6.0.0-vendor

---------- see libuhd version information above this line ----------

错误使用 reportSDRuStatus (第 106 行)

An error occurred: Could not execute UHD driver command in 'openDataConnection_c':

Non-default FPGA image detected on X310 device 0. Use sdruload to load the default FPGA image.

出错 comm.internal.SDRuBase/setupImpl

Release the hardware resources.

release(tx)

Answer 1

[Gavin Grant]

Alfred,

Many thanks for reaching out about the issue you encountered while attempting to use the comm.SDRuTransmitter and comm.SDRuReceiver system objects.

As indicated by the error message, the X310 had a non-default FPGA image loaded (likely the basebandTransmitter image, assuming you used that application beforehand). The comm.SDRuTransmitter and comm.SDRuReceiver objects require the default Ettus FPGA image to work.

Please run:

sdruload('Device','x310','IPAddress','192.168.40.2')

to load the default Ettus FPGA image. Then you can proceed to run the code you shared.

Note that basebandTransmitter (and other application objects) automatically load the required FPGA image. comm.SDRuTransmitter/comm.SDRuReceiver currently do not.

Best regards,

Gavin

[Alfred]

Thank you for your help.

Does comm.SDRuTransmitter and basebandTransmitter use same FPGA image version?

I think I have already load the FPGA image that can work with basebandTransmitter into the X310.

Thanks,

Alfred

[Gavin Grant]

Alfred,

To clarify, comm.SDRuTransmitter/SDRuReceiver use the Ettus default FPGA image; basebandTransmitter uses a non-default FPGA image. Therefore the FPGA image must be changed when moving between these applications.

basebandTransmitter will automatically load the required image, whereas comm.SDRuTransmitter/SDRuReceiver will only throw an error with instructions to manually load the default image via the sdruload function.

Best regards,

Gavin

[Alfred]

Gavin

Thank you. I solved my problem with your help.

By the way, I think the comm.SDRuTransmitter sends data to the X310, but the X310 will not actually generate RF signal until it has received enough data. Is this correct?

Can I transmit just several bits every time?

Thanks,

Alfred

[Gavin Grant]

Alfred,

That's great - glad that resolved the issue.

Regarding the RF transmission, the USRP will initiate a transmission each time the system object is stepped, i.e. each time you call tx(data). It will not buffer-up data unless you use burst mode transmission, documented here.

The basebandTransmitter application likewise does not enforce a minimum frame size, i.e. you can transmit several bits each time.

Best regards,

Gavin

[Alfred]

Gavin,

Thanks. I will use basebandTransmitter then.

Best regards,

Alfred