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Products => Test Equipment => Topic started by: Sparker on April 22, 2018, 01:49:49 pm

Title: Tektronix .tiq format question
Post by: Sparker on April 22, 2018, 01:49:49 pm

I wasn't able to find any reference on the Tektronix .tiq format structure, so I though I'd ask here.

So, we had to record continuous baseband IQ samples with a Tektronix RSA306B RSA. But I have a suspicion that the recorded data is not continuous but rather in blocks of N samples separated by many, many milliseconds between each other.  :-// Unfortunately I don't have the SignalVu software with me right now to check it.

I think so because if I open any of the .tiq files i see this:

Quote

      <DataDescription>
        <SamplingFrequency units="Hz">56000000</SamplingFrequency>
        <NumberSamples>484</NumberSamples>
        <SamplesType>IQ</SamplesType>
       ... other non important things
      </DataDescription>

Then there is a number of <DataSet> blocks. Every <DataSet> has a <TimestampOffset> field, which appears to me as the start time when this block was started being recorded. Every next DataSet's TimestampOffset is increased by about 10 milliseconds, that's what confuses me a lot:

Quote

<DataSet>
        <TriggerPosition units="Seconds">0.00000432142857142857</TriggerPosition>
        <TimestampOffset units="Seconds">0.078713250</TimestampOffset>
        <FastFrameID>-1</FastFrameID>
        <IDInFastFrame>-1</IDInFastFrame>
        <TotalInFastFrame>0</TotalInFastFrame>
        <Errors>
          <Error>
            <ID>2007</ID>
            <Message>Unaligned data</Message>
          </Error>
        </Errors>
      </DataSet>
      <DataSet>
        <TriggerPosition units="Seconds">0.00000432142857142857</TriggerPosition>
        <TimestampOffset units="Seconds">0.086891250</TimestampOffset>
        <FastFrameID>-1</FastFrameID>
        <IDInFastFrame>-1</IDInFastFrame>
        <TotalInFastFrame>0</TotalInFastFrame>
        <Errors>
          <Error>
            <ID>2007</ID>
            <Message>Unaligned data</Message>
          </Error>
        </Errors>
      </DataSet>
      <DataSet>
        <TriggerPosition units="Seconds">0.00000432142857142857</TriggerPosition>
        <TimestampOffset units="Seconds">0.097405822</TimestampOffset>
        <FastFrameID>-1</FastFrameID>
        <IDInFastFrame>-1</IDInFastFrame>
        <TotalInFastFrame>0</TotalInFastFrame>
        <Errors>
          <Error>
            <ID>2007</ID>
            <Message>Unaligned data</Message>
          </Error>
        </Errors>
      </DataSet>

So, could someone clarify this for me, please?