Quasi-Band-Limited Coronagraph for Extended Sources

A Coronagraph with a Band-Limited Mask for Finding Terrestrial Planets

Several recent designs for planet-finding telescopes use coronagraphs operating at visible wavelengths to suppress starlight along the telescope’s optical axis while transmitting any off-axis light from circumstellar material. We describe a class of graded coronagraphic image masks that can, in principle, provide perfect elimination of on-axis light, while simultaneously maximizing the Lyot sto...

Band-limited Functions: / / -convergence

Model synthesis for band-limited speech recognition

A recognizer trained with full-bandwidth speech performs badly when recognizing band-limited speech because of environment mismatch. In this paper, we have proposed a novel model synthesis method for band-limited speech recognition. It detects speech bandwidth automatically and synthesizes a new acoustic model only using a full-bandwidth model when the bandwidth has been changed. Experiments co...

ERRORLESS RESTORATION ALGORITHMS FOR BAND - LIMITED IMAGESPaulo

We consider the problem of restoring randomly distributed sets of missing pixels in band-limited discrete images , and give non-iterative and iterative algorithms capable of error-free restoration. The methods discussed have minimum dimension, that is, the size of the matrices and vectors which appear in the algorithm is determined by the number of unknown pixels. This is a characteristic which...

Quasi-Extended Asymptotic Functions

The class F of •quasi-extended asymptotic functions" introduced in the present paper contains all extended asymptotic functions [8, (3.1)] (in particular, all examples construct. ed in [9, Sec. 1 ]). But F contains also some new asymptotic functions very similar to tht Schwartz distributions. On the other hand , every two quasi-extended asymptotic func. tions can be multiplied as opposed to the...