+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

Averaging signals with random time shift and time scale fluctuations

Averaging signals with random time shift and time scale fluctuations

Methods of Information in Medicine 43(1): 13-16

Our main objective was to propose an alternative to the technique of signal averaging (SA) to avoid shape distortions due to jittering and scale fluctuations, leading to a mean shape signal rather than to an average one. In case of both time shift and time scale fluctuations of the individual signals, the first point was to show what model makes it possible to interpret their expected action as a linear shift invariant filter followed by a scale invariant one. So, even in the case of equal shape signals, the average is clearly not the same shape. The second point was to propose another averaging process, using the normalized integrals and called Shape Averaging (ShA) which provides, in this case, a mean signal preserving the common shape. The performances of ShA were firstly shown by simulation. Shifted and scaled versions of a given signal, without and with additive noise, have been generated at random. The mean shape signal obtained by ShA was compared to the shifted and scaled signal using the exact average values of the shifts and scale factors. A very good reconstruction of the mean shape signal is obtained for SNR = 20 dB and quite good for 8 dB, especially compared to SA. The method was then applied to a series of M-waves coming from surface EMG signals. In this case, the comparison of ShA with SA makes it possible to appreciate the validity of equal shape signal hypothesis.

Please choose payment method:

(PDF emailed within 1 workday: $29.90)

Accession: 048345354

Download citation: RISBibTeXText

PMID: 15026828

Related references

Up-scaling flow in fractured media: equivalence between the large scale averaging theory and the continuous time random walk method. Transport in Porous Media 43(3): 581-596, 2001

Nanosecond-regime correlation time scales for equilibrium protein structural fluctuations of metal-free cytochrome c from picosecond time-resolved fluorescence spectroscopy and the dynamic Stokes shift. Journal of Physical Chemistry. B 114(48): 15958-15968, 2011

Time alignment in the averaging of electro cardiographic signals. Jacobs, Jhairman). Proceedings Of The 8th International Conference On Medical And Biological Engineering And The 22nd Annual Conference On Engineering In Medicine And Biology (including The 4th Annual Meeting Of Aami). Xxiii: Chicago, Ill., U.s.a.). 16-1, 1969

Time Invariant Multi Electrode Averaging For Biomedical Signals. Proceedings of the ... IEEE International Conference on Acoustics, Speech, and Signal Processing. Icassp 2013: 1242-1246, 2014

Preferred paths or random VGPs during reversals? Can time-averaging explain both?. Physics and Chemistry of the Earth 23(7-8): 737-745, 1998

Random multiple scattering of ultrasound. II. Is time reversal a self-averaging process?. Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics 64(3 Pt 2): 036606-036606, 2001

Separation of lipid and water MR imaging signals by chopper averaging in the time domain. Radiology 165(1): 247-250, 1987

'Real time' transient averaging of cardiac synchronised signals and its application to the tooth pulse. Medical & Biological Engineering & Computing 28(1): 84-88, 1990

Assessing the effects of time and spatial averaging in 15N chemical shift/15N-1H dipolar correlation solid state NMR experiments. Journal of Biomolecular NMR 26(4): 283-295, August, 2003

Some statistical aspects of digital wiener filtering and detection of prescribed frequency components in time averaging of biological signals/. Biological Cybernetics 28(1): 55-61, 1977

Averaging semiempirical NMR chemical shifts: dynamic effects on the subpicosecond time scale. Journal of Physical Chemistry. A 113(43): 11723-11733, 2010

Averaging Fluctuations in Resolvents of Random Band Matrices. Annales Henri Poincaré 14(8): 1837-1926, 2013

Artificial time-averaging and the recovery of ecological signals preserved in the subfossil record; linking the temporal scales of ecology and paleoecology. Abstracts with Programs - Geological Society of America 31(7): 356, 1999