Propane spectral resolution enhancement by the maximum entropy method.
The Burg algorithm for maximum entropy power spectral density estimation is applied to a time series of data obtained from a Michelson interferometer and compared with a standard fast Fourier transform (FFT) estimate for resolution capability. The propane transmittance spectrum was estimated by use of the FFT with a 2(18)-data sample interferogram, giving a maximum unapodized resolution of 0.06 cm(-1). This estimate was then interpolated by zero filling an additional 2(18) points, and the final resolution was taken to be 0.06 cm(-1). Comparison of the maximum entropy method (MEM) estimate with the FFT was made over a 45-cm(-1) region of the spectrum for several increasing record lengths of interferogram data beginning at 2(10). It is found that over this region of 45 cm(-1), the MEM estimate with 2(16) data samples is in close agreement with the FFT estimate using 2(18) samples.
Bonavito
N L
NL
Yeh
K C
KC
Stewart
K P
KP
Inguva
R
R
Hurley
E J
EJ