V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

SNR
       Serial NumbeR (IMEI, GSM, mobile-systems)


V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

SNR
       Signal-to-Noise Ratio


The Free On-line Dictionary of Computing (30 December 2018):

signal-to-noise ratio
SNR
S/N ratio

   1.  (SNR, "s/n ratio", "s:n ratio") "Signal"
   refers to useful information conveyed by some communications
   medium, and "noise" to anything else on that medium.  The
   ratio of these is usually expressed logarithmically, in
   decibels.

   2.  The term is often applied to Usenet
   newsgroups though figures are never given.  Here it is quite
   common to have more noise (inappropriate postings which
   contribute nothing) than signal (relevant, useful or
   interesting postings).  The signal gets lost in the noise
   when it becomes too much effort to try to find interesting
   articles among all the crud.  Posting "noise" is probably the
   worst breach of netiquette and is a waste of bandwidth.

   [Jargon File]

   (1996-01-29)