Practical multi-spectrum Hadamard transform spectrometer

Abstract

We have constructed a Hadamard Transform Spectrometer (HTS) which simultaneously obtains fifteen infrared spectra, each having 255 spectral elements.Spectra are obtained essentially in real time through use of a minicomputer with 8K words of memory and a CRT display. This permits operation of the instrument in the field.

Stellar Spectroscopy Technique on Small- and Intermediate-Diameter Telescopes

“…In the case of extended objects a combination of coding masks at the entrance to and exit from the spectrometer can be used [104]. An Hadamard spectrometer allowing simultaneous acquisition of 15 IR spectra each consisting of 255 elements [105] was used to study the latitudinal distribution of methane across the disk of Jupiter.…”

Chasing White-Light Flares

“…My brief career in infrared astronomy had equipped me with an awareness of the mathematics of difference sets, Hadamard transforms, and Walsh functions, which enabled comparable multiplex advantages for one-dimensional spectroscopy in certain applications (e.g. Tai et al, 1975). Despite this I had failed, at a cost of many crumpled napkins, to figure out the URA trick that makes this optimization work in two dimensions.…”