Time averaging. Does the noise really average toward zero?

✍ Scribed by Traficante, Daniel D.

• Publisher: John Wiley and Sons
• Year: 1991
• Tongue: English
• Weight: 327 KB
• Volume: 3
• Category: Article
• ISSN: 1043-7347
• DOI: 10.1002/cmr.1820030203

✦ Synopsis

Abstract

Time averaging is used widely in Fourier transform NMR spectroscopy. Yet there is a popular misconception of how the process increases the overall signal‐to‐noise (S/N) ratio of a spectrum. The common, but incorrect, explanation assumes that when noise is added to noise, the overall result averages toward zero. This article first shows that this explanation cannot be valid and then presents a detailed analysis of time averaging, including a mathematical derivation of the well‐known result that time averaging increases the S/N by the square root of the number of scans averaged.