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Question about UMX RRS feed

  • Question

  • I have received data by UMX. when I analyse the data, I find that the receiving data is not continuous. How to solve this problem?
    Thursday, March 17, 2011 2:10 AM

Answers

  • Hi, Guys:

    The interval of signal in UMX should be much shorter than using DUT. If not, please check you code. Thanks.

    Regards

    Sen


    Sen Xiang (项森)
    • Marked as answer by Sen Xiang Thursday, March 31, 2011 8:48 AM
    Tuesday, March 29, 2011 9:27 AM

All replies

  • Hi, Taozhou:

    Make sure sender can send signal continuously . Thanks.

    Regards

    Sen


    Sen Xiang (项森)
    Friday, March 18, 2011 2:22 PM
  • Thank you very much for your reply!

    The sender is Sora in UMX, I know the signal transmitted by UMX is not continuous, because it only transmit data with 2MB once a time. So,I want to ask you a question, If I use the vector signal generator to transmit data to the Sora, it can receive the data continuously and doesn't lose the packet or some data in this UMX mode ?

    I am looking foward to your reply.

    Saturday, March 19, 2011 1:25 AM
  • Not exactly. the interval between each signal might be caused by your modulation code, or in other words, if you precache your signal, and transmit it continously, the receiver can get it continously. Thanks.
    Sen Xiang (项森)
    Saturday, March 19, 2011 12:48 PM
  • I doubt that the performance of UMX mode is not good as the kernel mode.

    if I transmit signal continuously, I can receive it continuously in UMX mode or kernel mode.  Are you sure this point?

    Thanks.

    Sunday, March 20, 2011 10:49 AM
  • Hello, taozhou,

     

    Have you solve the problem of signal continuity?

    I'm also using UMX recently. I'm also confused with the continuous of signal. 

    I use UMX to transmit a signal from a file. I'm not sure the signal I transmit is continuous. Maybe I should use a signal generator to do a test. 

    The signal I received has a lot of values close to zero. What I sent is BPSK signal.

    My hardware is also SORA + USRP adapter + XCVR2450. 

     

    Hope to communicate with you. Recently I'll work on SORA, as a beginner. 

    Lin

    Thursday, March 24, 2011 10:49 AM
  • Hello, taozhou,

     

    Have you solve the problem of signal continuity?

    I'm also using UMX recently. I'm also confused with the continuous of signal. 

    I use UMX to transmit a signal from a file. I'm not sure the signal I transmit is continuous. Maybe I should use a signal generator to do a test. 

    The signal I received has a lot of values close to zero. What I sent is BPSK signal.

    My hardware is also SORA + USRP adapter + XCVR2450. 

     

    Hope to communicate with you. Recently I'll work on SORA, as a beginner. 

    Lin

    Hi,

    If you use the UMX to transmit the data,  it is not continue because of the limitation of 2M file. The interval is noise of about 400 samples. You can use the vector signal generator to send a sina signal continuously, and then checking  the receiving wave.

     

     

    Saturday, March 26, 2011 4:24 AM
  • Hi, Taozhou,

    I changed to use DUT to transmit the signal. It seems continuous now. 

    Does this mean UMX cannot be used to do real-time processing? Is UMX only a tool for debugging? The final version must be implemented in kernel-mode, right?

    Lin 

    Monday, March 28, 2011 5:11 AM
  • I have tried to transmit the signal by DUT tool, however it is aslo not continuous. Are you sure it is continuous?

    Maybe the problem can be solved in kernel-mode.

     

    Monday, March 28, 2011 12:34 PM
  • Hi, Guys:

    The interval of signal in UMX should be much shorter than using DUT. If not, please check you code. Thanks.

    Regards

    Sen


    Sen Xiang (项森)
    • Marked as answer by Sen Xiang Thursday, March 31, 2011 8:48 AM
    Tuesday, March 29, 2011 9:27 AM
  • Hi taozhou,

    I read the received dump file in Matlab. The waveform seems continuous, but I'm not sure.

    What I send is a random BPSK signal. Use Matlab generated a random BPSK signal. The number of BPSK symbol is 128, and the over sampling rate is 16, so the total number of complex samples is 128*16=2048. The base band bandwidth should be 44M/16~=2.75M. Use DUT to transmit and receive the signal, then use Matlab to read the file.

    I want to do correlation with the transmitted and received signals. But I failed. The frequency offset seems too large. I cannot get the correlation peak. Another strange thing is, I found high amplitude short burst in each 2048-sample period.

    Does this forum not support attachment? I can share the data file with you. Gmail is not stable recently. So give you my 163 email, huanglin_bupt@163.com. 

     

    Lin

    Wednesday, March 30, 2011 4:06 AM