SpectrumDeconvolution: Improvement of the resolution in spectra, decomposition of...

Description Usage Arguments Details Value Author(s) References

View source: R/zzz.R

Description

This function is used to strip-off known instrumental function from source spectrum. It is achieved by deconvolution of source spectrum according to response spectrum using Gold or Richardson-Lucy algorithms. Both methods provides less osccillating solutions than Fourier or VanCittert algorithms.

Usage

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SpectrumDeconvolution(y,response,iterations=10,repetitions=1,
                      boost=1.0,method=c("Gold","RL"))

Arguments

y

numeric vector of source spectrum

response

vector of response spectrum. Its length shold be less or equal the length of y

iterations

number of iterations (parameter L in the Gold deconvolution algorithm) between boosting operations

repetitions

number of repetitions of boosting operations. It must be greater or equal to one. So the total number of iterations is repetitions*iterations

boost

boosting coefficient/exponent. Applies only if repetitions is greater than one. Recommended range [1..2].

method

method selected for deconvolution. Either Gold or Richardson-Lucy

Details

Both methods search iteratively for solution of deconvolution problem

y(i)=∑_{j=1}^{n}h(i-j)x(j)+e(i)

in the form

x^{(k)}(i)=M^{(k)}(i)x^{(k-1)}(i)

For Gold method:

M^{(k)}(i)=\frac{x^{(k-1)}(i)}{∑_{j=1}^{n}h(i-j)x^{(k-1)}(j)}

For Richardson-Lucy:

M^{(k)}(i)=∑_{l=0}^{n}h(i-l)\frac{x^{(k-1)}(l)}{∑_{j=1}^{n}h(l-j) x^{(k-1)}(j)}

Boosting is the exponentiation of iterated value with boosting coefficient/exponent. It is generally improve stability.

Value

Numeric vector of the same length as y with deconvoluted spectrum.

Author(s)

Miroslav Morhác

References

Abreu M.C. et al., A four-dimensional deconvolution method to correct NA38 experimental data, NIM A 405 (1998) 139.

Lucy L.B., A.J. 79 (1974) 745.

Richardson W.H., J. Opt. Soc. Am. 62 (1972) 55.

Gold R., ANL-6984, Argonne National Laboratories, Argonne Ill, 1964.

Coote G.E., Iterative smoothing and deconvolution of one- and two-dimensional elemental distribution data, NIM B 130 (1997) 118.

M. Morhác, J. Kliman, V. Matousek, M. Veselský, I. Turzo.: Efficient one- and two-dimensional Gold deconvolution and its application to gamma-ray spectra decomposition. NIM, A401 (1997) 385-408.

Morhác M., Matousek V., Kliman J., Efficient algorithm of multidimensional deconvolution and its application to nuclear data processing, Digital Signal Processing 13 (2003) 144.


Peaks documentation built on May 29, 2017, 8:29 p.m.