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Bhatia, Manjit S.

Publications and source records attributed to Bhatia, Manjit S..

Power spectral estimation algorithms

Algorithms to estimate the power spectrum using Maximum Entropy Methods were developed. These algorithms were coded in FORTRAN 77 and were implemented on the VAX 780. The important considerations in this analysis are: (1) resolution, i.e., how close in frequency two spectral components can be spaced and still be identified; (2) dynamic range, i.e., how small a spectral peak can be, relative to the largest, and still be observed in the spectra; and (3) variance, i.e., how accurate the estimate of the spectra is to the actual spectra. The application of the algorithms based on Maximum Entropy Methods to a variety of data shows that these criteria are met quite well. Additional work in this direction would help confirm the findings. All of the software developed was turned over to the technical monitor. A copy of a typical program is included. Some of the actual data and graphs used on this data are also included.

Bhatia, Manjit S.

Holographic gratings for spectrographic applications: Study of abberations

A computer program was developed that determines the optimum holographic grating recording parameters as a function of optical instrumental parameters and desired wavelength range for Seya-Namioka monochromator mountings. The theory and basic equations for designing holographic concave gratings such that minimization of aberrations of astigmatism or coma over a desired wavelength range may be achieved are presented. The computer program is described, including all of the subroutines. The input data, definitions of terms, and data card description are presented. An example is summarized for using the program and the output data is described in detail.

Bhatia, Manjit S.