Fast exponential fitting algorithm for real-time instrumental use

Abstract

We report on a very fast fitting algorithm for single exponential functions which is based on the method of successive integration. The algorithm corrects the systematic error of trapezoidal integration. The new algorithm needs only 150 μs for a dataset of 1536 points and is around 700 times faster than the nonlinear Levenberg–Marquardt fit provided by LABVIEW. This makes it suitable for real-time instrumental use. Beside the better time resolution, the acceleration allows more averaging, which leads to higher precision. In our experiment instrumental sensitivity was improved by a factor of 3.7.