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arXiv · 1510.09105

Theoretical Framework and Simulation Results for Implementing Weighted Multiple Sampling in Scientific CCDs

Cristobal Alessandri·Dani Guzman·Angel Abusleme·Diego Avila·Enrique Alvarez·Hernan Campillo·Alexandra Gallyas·Christian Oberli·Marcelo Guarini
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Abstract

The Digital Correlated Double Sampling (DCDS) is a technique based on multiple analog-to-digital conversions of every pixel when reading a CCD out. This technique allows to remove analog integrators, simplifying the readout electronics circuitry. In this work, a theoretical framework that computes the optimal weighted coefficients of the pixels samples, which minimize the readout noise measured at the CCD output is presented. By using a noise model for the CCD output amplifier where white and flicker noise are treated separately, the mathematical tool presented allows for the computation of the optimal samples coefficients in a deterministic fashion. By modifying the noise profile, our simulation results get in agreement and thus explain results that were in mutual disagreement up until now.

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Cristobal Alessandri, Dani Guzman, Angel Abusleme, Diego Avila, Enrique Alvarez, Hernan Campillo, Alexandra Gallyas, Christian Oberli, Marcelo Guarini. 2015-10-30. Theoretical Framework and Simulation Results for Implementing Weighted Multiple Sampling in Scientific CCDs. https://arxiv.org/abs/1510.09105

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