Signal to noise ratio with SNAP


is it possible to calculate the SNR (TDX, TSX) with SNAP? I am able to process the Sigma0 band with the calibration tool, but are there any tools to calculate the noise equivalent sigma zero (NESZ)?

Thank you in advanced!


NESZ should be specified in the TerraSAR product descriptions or equivalent documents.

Hello Mengdahl,

thank you very much for your reply. I got the specification for each channel in the form of a set of seven polynomial coefficients, but I don’t know how to interpret or use these coefficients to calculate the SNR with the formula

for each channel. If you’d like to help me with that, I’d be very happy!

Thank you

I found a record called “averageNoiseRecordAzimuthSpacing” with the value = 1.50349748134613037E+00 (TDX, HH). Is it suitable if I use this as NESZ for the specific channel?

Just find the max NESZ value for each mode/beam from TSX/TDX documentation and use that - in most cases you will be working way above the noise-floor unless you are looking at dead-calm water.

Hi Peter;
I am curious to know in what paper/book/report/manual you found the shown SNR definition.
I’m asking because, from an application perspective it makes sense so subtract the NESZ from sigma naught (in the numerator) however the ‘traditional electrical engineering’ definition of SNR does not do so, i.e. it is simply the ratio of sigma naught over the NESZ (in other words the signal is considered to be noise free). I saw SNR defined in the way you show in a recent paper by J.M. Lopez-Sanchez et al., RS of Env, no.192, 2017, pp.30-44 but they didn’t include a reference and I’m thinking there must be one that predates their paper, ideally, in some respected handbook.
Thank you

Hi there,

Does anyone know how to calculate the signal to noise ratio with Sentinel-1 GRD products in SNAP?


Hello everyone,

I also wondering how to generate SNR and Local Incidence angle of TanDEM-X data using SNAP?