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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 RSP2 and RSP2pro also provide SDRuno software for Windows which enables very accurate RF power measurements to be made anywhere between 1 kHz and 2 GHz. 

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


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:


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


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


Check out the video


Or visit the SDRplay YouTube Channel


Long history in semiconductors (including Texas Instruments and CSR) + co-founder of SDRplay Ltd.