[Discuss-gnuradio] Estimating SNR (was: Re: query)

[Marcus Müller]

SNR is signal strength/noise

Yeah, obviously, but what does that mean? how can you *describe* signal strength with a mathematical formula based on the digital samples you have in GNU Radio?

The point is that you'll just need an estimator for the signal energy, and an estimator for the noise power.

There's a lot of estimators for both; for a single tone, Welch's method might be pretty usable. Another approach would be a narrow filter, and a signal-to-magnitude-squared converter.
For noise power, you could just calculate the overall receive signal power, and subtract the signal power estimate.

Best regards,
Marcus

On 11.05.2016 11:56, Raja Muneeba wrote:

SNR is signal strength/noise

From: Marcus Müller <address@hidden>
Date: Wednesday 11 May 2016 12:48
To: Raja Muneeba <address@hidden>, "address@hidden" <address@hidden>
Subject: Re: query

Hi Muneeba,

so the point is: What *is* SNR? Can you define it mathematically?

Best regards,
Marcus

On 11.05.2016 11:47, Raja Muneeba wrote:

HI,

I am using usrp N210 with db SBX, and I do not have any message wave (or source file). I simply transmit and receive a sin wave via USRPs (find my graphs attached). I am not doing any modulation/de modulations.

I need to know the SNR value at the receiver end. I also want to adjust the signal strength to change SNR. SNR is signal strength/noise in db. How can I do this?

I see solutions with modulation schemes, but since I don’t use any modulation, how can it be done without that?

Regards,

Muneeba R.