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Using a low-cost SDR for logging accurate RF power and SNR measurements

The ability to make a log of absolute RF power levels centred at a given frequency, and of selectable bandwidth,  over specified time intervals is a very powerful capability.  Even more so, in portable or mobile situations such as field strength monitoring of both wanted and unwanted signals where an accurate, yet simple and low-cost solution is desirable.  

Even in the lab, using expensive general purpose RF gear for long running projects is undesirable when the use of a low-cost alternative will work just as well.

SDRplay – makers of the RSP family of SDRs also provide SDRuno software for Windows which enables very accurate RF power measurements (within +/- 1dBm) and SNR readings   to be made anywhere between 1kHz and 2GHz. 
 RFpowerLogging_c58a745a4e25dffcb5fe5f407fe20ea7ae3a399b.jpg

With SDRuno, the user can select the bandwidth over which the power readings are to be taken – See below: 192kHzSlice_2a5ccb3a25da5af226ee6bce3f50a4552cf77076.jpg

 

The next thing to do is select the time interval for the logging which can be varied from every second to every 1800 seconds as shown below:
 RFpowertimeintervalselect_311fd30508c4a05c23cb65adf272f0570f1b4710.jpg

 

Once the logger has started, measurements of RF power level and SNR are taken at the specified intervals:
 RFpower_logwaterfall_360239236b5fc3a7f5b55b5bed4ee4fd4575535c.jpg

 

The readings are stored and can be outputted to a .csv file for further analysis or charting purposes:
 RFpowerCSVfile_f0197aa02ac7d0b4245090b382acc760a176796f.jpg

  

Check out the video

 

Or visit the SDRplay YouTube Channel

Simply google "RS Components RSP2pro"  to get a link to your local RS Components SDRplay webpage - from there, you have links to the other members of the SDRplay RSP family. Accurate power measurement and logging is now also supported on the RSP1A   

Design, marketing and business background in semiconductors (including Texas Instruments and CSR), then co-founder and now sales and marketing director at SDRplay Ltd.