30 research outputs found
Design and analysis of efficient synthesis algorithms for EDAC functions in FPGAs
Error Detection and Correction (EDAC) functions have been widely used for protecting memories from single event upsets (SEU), which occur in environments with high levels of radiation or in deep submicron manufacturing technologies. This paper presents three novel synthesis algorithms that obtain areaefficient implementations for a given EDAC function, with the ultimate aim of reducing the number of sensitive configuration bits in SRAM-based Field-Programmable Gate Arrays (FPGAs). Having less sensitive bits results in a lower chance of suffering a SEU in the EDAC circuitry, thus improving the overall reliability of the whole system. Besides minimizing area, the proposed algorithms also focus on improving other figures of merit like circuit speed and power consumption. The executed benchmarks show that, when compared to other modern synthesis tools, the proposed algorithms can reduce the number of utilized look-up tables (LUTs) up to a 34.48%. Such large reductions in area usage ultimately result in reliability improvements over 10% for the implemented EDAC cores, measured as MTBF (Mean Time Between Failures). On the other hand, maximum path delays and power consumptions can be reduced up to a 17.72% and 34.37% respectively on the placed and routed designs.This work was supported by the Spanish Ministry of Educacion, Cultura y Deporte under the grant FPU12/05573, and by the Spanish Ministry of Economıa project ESP2013-48362-C2-2-P, in the frame of the activities of the Instrument Control Unit of the Infrarred Instrument of the ESA Euclid Mission carried out by the Dept. of Electronics and Computer Technology of the Universidad Politécnica de Cartagen
The adaptive optics lucky imager (AOLI): presentation, commissioning, and AIV innovations
Here we present the Adaptive Optics Lucky Imager (AOLI), a state-of-the-art
instrument which makes use of two well proved techniques, Lucky Imaging (LI)
and Adaptive Optics (AO), to deliver diffraction limited imaging at visible
wavelengths, 20 mas, from ground-based telescopes. Thanks to its revolutionary
TP3-WFS, AOLI shall have the capability of using faint reference stars. In the
extremely-big telescopes era, the combination of techniques and the development
of new WFS systems seems the clue key for success. We give details of the
integration and verification phases explaining the defiance that we have faced
and the innovative and versatile solutions for each of its subsystems that we
have developed, providing also very fresh results after its first fully-working
observing run at the William Herschel Telescope (WHT).Comment: 6 pages, 6 figures, conference. arXiv admin note: text overlap with
arXiv:1703.09354, arXiv:1608.0480
Covariance of lucky images for increasing objects contrast: Diffraction-limited images in ground-based telescopes
Images of stars adopt shapes far from the ideal Airy pattern due to atmospheric density fluctuations. Hence, diffraction-limited images can only be achieved by telescopes without atmospheric influence, e.g. spatial telescopes, or by using techniques like adaptive optics or lucky imaging. In this paper, we propose a new computational technique based on the evaluation of the COvariancE of Lucky Images (COELI). This technique allows us to discover companions to main stars by taking advantage of the atmospheric fluctuations. We describe the algorithm and we carry out a theoretical analysis of the improvement in contrast. We have used images taken with 2.2-m Calar Alto telescope as a test bed for the technique resulting that, under certain conditions, telescope diffraction limit is clearly reached.This research was supported by the Ministerio de Economía y Competitividad under project FIS2012-31079 and the Fundación Séneca of Murcia under projects 15419/PI/10 and 15345/PI/10
An instrumental puzzle: the modular integration of AOLI
The Adaptive Optics Lucky Imager, AOLI, is an instrument developed to deliver
the highest spatial resolution ever obtained in the visible, 20 mas, from
ground-based telescopes. In AOLI a new philosophy of instrumental prototyping
has been applied, based on the modularization of the subsystems. This modular
concept offers maximum flexibility regarding the instrument, telescope or the
addition of future developments.Comment: 10 pages, 8 figures, Proc. SPIE 9908, Ground-based and Airborne
Instrumentation for Astronomy VI, 99082Z (August 9, 2016
The control unit of the near infrared spectrograph of the Euclid space mission: detailed design
The Near Infrared Spectrograph and Photometer (NISP) is one of the instruments on board the ESA EUCLID mission. The Universidad Polit´ecnica de Cartagena and Instituto de Astrof´ısica de Canarias are responsible of the Instrument Control Unit of the NISP (NI-ICU) in the Euclid Consortium. The NI-ICU hardware is developed by CRISA (Airbus Defence and Space), and its main functions are: communication with the S/C and the Data Processing Unit, control of the Filter and Grism Wheels, control of the Calibration Unit and thermal control of the instrument. This paper presents the NI-ICU status of definition and design at the end of the detailed design phase. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.The authors want to acknowledge the contributions provided by the NISP system team of the Euclid Consortium to this work. This work has been supported by the Spanish Ministry of Economy under the projects ESP2013-48362-C2-2-P, ESP2014-56869-C2-2-P and ESP2015-69020-C2-2-R, as well as by ERDF funds from the European Commission
Laboratory and telescope demonstration of the TP3-WFS for the adaptive optics segment of AOLI
AOLI (Adaptive Optics Lucky Imager) is a state-of-art instrument that combines adaptive optics (AO) and lucky imaging (LI) with the objective of obtaining diffraction limited images in visible wavelength at mid- and big-size ground-based telescopes. The key innovation of AOLI is the development and use of the new TP3-WFS (Two Pupil Plane PositionsWavefront Sensor). The TP3-WFS, working in visible band, represents an advance over classical wavefront sensors such as the Shack-Hartmann WFS (SH-WFS) because it can theoretically use fainter natural reference stars, which would ultimately provide better sky coverages to AO instruments using this newer sensor. This paper describes the software, algorithms and procedures that enabled AOLI to become the first astronomical instrument performing real-time adaptive optics corrections
in a telescope with this new type of WFS, including the first control-related
results at the William Herschel Telescope (WHT)This work was supported by the Spanish Ministry of Economy under the projects AYA2011-29024, ESP2014-56869-C2-2-P, ESP2015-69020-C2-2-R and DPI2015-66458-C2-2-R, by project 15345/PI/10 from the Fundación Séneca, by the Spanish Ministry of Education under the grant FPU12/05573, by project ST/K002368/1 from the Science and Technology Facilities Council and by ERDF funds from the European Commission. The results presented in this paper are based on observations made with the William Herschel Telescope operated on the island of La Palma by the Isaac Newton Group in the Spanish Observatorio del Roque de los Muchachos of the Instituto de Astrofísica de Canarias. Special thanks go to Lara Monteagudo and Marcos Pellejero for their timely contributions
Covariance of lucky images: Performance analysis
The covariance of ground-based lucky images is a robust and easy-to-use algorithm that allows us to detect faint companions surrounding a host star. In this paper, we analyse the relevance of the number of processed frames, the frames' quality, the atmosphere conditions and the detection noise on the companion detectability. This analysis has been carried out using both experimental and computer-simulated imaging data. Although the technique allows us the detection of faint companions, the camera detection noise and the use of a limited number of frames reduce the minimum detectable companion intensity to around 1000 times fainter than that of the host star when placed at an angular distance corresponding to the few first Airy rings. The reachable contrast could be even larger when detecting companions with the assistance of an adaptive optics system.This research was supported by the Ministerio de Economía y Competitividad under project FIS2012-31079. We would like to thank the technical staff of the Calar Alto Observatory in Spain for all its help with the observations
AOLI: Near-diffraction limited imaging in the visible on large ground -based telescopes
The combination of Lucky Imaging with a low order adaptive optics system was demonstrated very successfully on the Palomar 5m telescope nearly 10 years ago. It is still the only system to give such high-resolution images in the visible or near infrared on ground-based telescope of faint astronomical targets. The development of AOLI for deployment initially on the WHT 4.2 m telescope in La Palma, Canary Islands, will be described in this paper. In particular, we will look at the design and status of our low order curvature wavefront sensor which has been somewhat simplified to make it more efficient, ensuring coverage over much of the sky with natural guide stars as reference object. AOLI uses optically butted electron multiplying CCDs to give an imaging array of 2000 x 2000 pixels.Science and Technology Facilities CouncilThis is the author accepted manuscript. The final version is available from SPIE via http://dx.doi.org/10.1117/12.223090