Hadamard transform spectroscopy

Hanley, Q. S., Verveer, P. J. and Jovin, T. M. (1999). Spectral imaging in a programmable array microscope by hadamard transform fluorescence spectroscopy. Appl. Spectrosc. 53, 1-10. 

Maximum length binary sequences (MLBSs) of length N = 2l-l, where I is a positive integer, have a perfectly flat power spectrum [77]. The deconvolution in Eq. (61) can be computed very efficiently by means of a fast Hadamard transform, and they have, for example, been employed for Hadamard NMR spectroscopy [78]. 

Hadamard transform spectroscopy existed long before Raman imaging, as a form of multiplex spectroscopy. A Hadamard mask is an array of clear and... 

Stochastic excitation with m sequences and the use of the Hadamard transformation have been investigated in NMR spectroscopy [Kail, Zie2] as well as in NMR imaging [Chal]. Processing of the nonlinear response to m sequences by Hadamard and Fourier transformation results in signal distortions reminiscent of noise, which are caused by the nonlinear parts of the response [B1U2]. 

Two methods of recovering spectra by use of complex mathematical methods are known as Hadamard transform and Fourier transform spectroscopy. Both have been applied successfully to infrared spectroscopy. 

For a description of the Hadamard transform and Hadamard tran.dorm spectroscopy, see D. K. Graff. J. Chem. duc.. 1995, 72. 304, Fourier. Hadamard. and Hilheri Transforms in Chemisirv.A. G. Marshall, cd. New York Plenum Press. 1982. 

R. M. Hammaker, R. A. DeVerse, D. J. Asunskis, W. G. Fateley. Hadamard transform near-infrared spectrometers. In Handbook of Vibrational Spectroscopy, J. M. Chalmers, P. R. Griffiths, eds. John Wiley Sons Ltd., Chichester, West Susses, UK, 1 453-460, 2002. 

JF Turner II, PJ Treado. Near-infrared acousto-optic tunable filter Hadamard transform spectroscopy. Appl Spectrosc 50 277, 1996. 

Kaiser, R., Application of the Hadamard Transform to NMR Spectroscopy with Pseudonoise Excitation , J. Magn. Reson. 1974,15, 44—63. 

Hanley, Q. S., Masking, Photobleaching, and Spreading Effects in Hadamard Transform Imaging and Spectroscopy Systems , A/y Z. Spectrosc. 2001, 55, 318-330. 

Hadamard NMR spectroscopy [3] is based on the Hadamard Transform rather than the more conventional Fourier Transform. The NMR frequencies are encoded using the Hadamard matrices and multiply-selective frequency encoding pulses. Only the frequencies of interest are used at the encoding stage. Thus vast spectral regions that contain no interesting information can be excluded and the correlation spectra can be recorded much faster. Some prior knowledge about the peak positions in the indirectly detected dimensions is required for these experiments. 

Kauppinen, J., Partanen, J. Fourier Transforms in Spectroscopy. Wiley, New York (2001) Marshall, A.G. (ed.) Fourier, Hadamard, and Hilbert Transforms in Chemistry. Plenum Press,... 

HADAMARD AND OTHER DISCRETE TRANSFORMS IN SPECTROSCOPY N. J. A. Sloane... 

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