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Sample rate

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The initial sample rate is adjusted, based on tuner settings, to significantly over-sample the input signal.  After digital mixing and filtering, the effective sample rate of the data saved to disk is twice the bandwidth selected when the file was collected.  The bandwidth and sample rate values are embedded in the QVRT context fields.

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The initial sample rate is adjusted, based on tuner settings, to significantly over-sample the input signal.  After digital mixing and filtering, the effective sample rate of the data saved to disk is twice the bandwidth selected when the file was collected.  The bandwidth and sample rate values are embedded in the QVRT context fields.

​In release 2.4 (Expected early June), we anticipate that users will be able to set an effective sample rate they want in the output data independently of the collected bandwidth. This feature will allow a 10 MHz LTE signal to be sampled at 30.72MHz for digital processing of the file.  

This does not mean we will not, as discussed by Gene, over sample the input signal at the A/D even in this case.  Rather, it means we'll allow the user control of the logged sample rate in the file and in the API streams and not necessarily all the behind the scenes processing that generates it.  The goal of the WBT is to make it easy to use by the 'end user', and to provide output files of the format desired with minimal the chance of error.  To make that possible, our RF engineers simplify many of the "hard" things (like amplification, mixing, and filtering) that cause problems with other radio systems to focus on getting the best possible data to the output file.  We think this is a positive value-added approach to building a Software Defined Platform, not simply releasing a Software Defined Radio.  This Tech Note: https://www.qrctech.com/Articles.asp?ID=285 may interest anyone wanting to read more about all the things the WBT takes care of "Behind the Scenes" to make the product the easy to use end-user field employable solution it is.  

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