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DeadEnd's avatar
DeadEnd
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2 years ago

Questions about BER Data Rate.

Hi, I’m currently carrying out an evaluation in which I measure the Bit Error Rate(BER) of an RG174 cable using Stratix and then utilized this data to generate an Eye diagram for signal integrity ve...
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Kshitij_Intel's avatar
Kshitij_Intel
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2 years ago

Hi Junsu,

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  • Could the Data Rate specified in Qsys(e.g., 6Gbps) not be the actual bits being transferred? Might it be considering all the internal data exchanges, inclusive of the BER pre-calculation? (The reason I’m inquiring is my curiosity on whether applying a 6Gbps rate to a cable with 3GB max frequency is technically queried as an over-spec situation)

[KG] - Your maximum frequency will limit the data rate. It is not feasible to send 6Gbps data rate at 3GHz.

  • If so, could you explain what roles the additional bits ply in the Data Rate, aside from the bits actually transmitted through the cable?

[KG] - Can you explain how are you calculating the number of bits transmitted and received for a specific time duration for the IP?


Thank you,

Kshitij Goel

​


  • DeadEnd's avatar
    DeadEnd
    Icon for New Contributor rankNew Contributor
    2 years ago

    Hi, thank you and sorry for late response,

    1. You said that it is not possible to transmit 6Gbps data on a 3Ghz cable, does this mean that when Qsys sends and receives data, it does not send and receive data when it is falling, but only when it is rising?

    2. When measuring the BER, I coded the verilog to time each sampling point and indicate the bits sent and received at that time.
    I then calculated the BER by adding up all the bits and dividing by the total time. Attached is example of measured data.