Health & Environmental Research Online (HERO)


Print Feedback Export to File
3334240 
Journal Article 
Comparison of FFT and LMS applied to photoacoustic signal detection - art. no. 69370Z 
Starecki, T; Owczarek, T 
2007 
Unk 
Proceedings of SPIE
ISSN: 0277-786X
EISSN: 1996-756X 
PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS (SPIE) 
6937 
Z9370-Z9370 
WOS:000254566700036 
Photoacoustic measurements are quite often performed by means of data acquisition systems that collect samples of the photoacoustic signal, and use the samples for the purpose of calculation of the amplitude of its fundamental frequency. The most common method of such calculations is the FFT, but the amplitude can be also obtained by means of the least mean square (LMS) method. The paper compares properties of both methods from the point of view of their numerical efficiency and errors vs. S/N ratio and number of samples per period of the investigated signal. The discussion shows that in the case of an integer number of periods sampled, results of the FFT and LMS are identical, but due to higher numerical efficiency the LMS method should be used. 
photoacoustics; FFT; DFT; least-squares; three-parameter sine fit