We propose a new powerful scalable generic parallel and modular architecture well suited to LDPC code decoding. This architecture template has been instantiated in the case of the 802.16e WiMax standard. The proposed design is fully compliant with all the code classes defined by the standard. It has been validated through an implementation on a Xilinx Virtex5 FPGA component. A four or six-module FPGA design yields a throughput ranging from 10 to 30 Mbit/s by means of 20 iterations at a clock frequency of 160 MHz which mostly satisfies communication throughput in the case of the WiMax Mobile communication.

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In many spatial systems, image is a core technology to fulfil the mission requirements. Depending on the application, the needs and the constraints are different and imaging systems can offer a large variety of configurations in terms of wavelength, resolution, field-of-view, focal length or sensitivity. Adequate image processing algorithms allow the extraction of the needed information and the interpretation of images. As a prime contractor for many major civil or military projects, Astrium ST is very involved in the proposition, development and realization of new image-based techniques and systems for space-related purposes. Among the different applications, space surveillance is a major stake for the future of space transportation. Indeed, studies show that the number of debris in orbit is exponentially growing and the already existing population of small and medium debris is a concrete threat to operational satellites. This paper presents Astrium ST activities regarding space surveillance for space situational awareness (SSA) and space traffic management (STM). Among other possible SSA architectures, the relevance of a ground-based optical station network is investigated. The objective is to detect and track space debris and maintain an exhaustive and accurate catalogue up-to-date in order to assess collision risk for satellites and space vehicles. The system is composed of different type of optical stations dedicated to specific functions (survey, passive tracking, active tracking), distributed around the globe. To support these investigations, two in-house operational breadboards were implemented and are operated for survey and tracking purposes. This paper focuses on Astrium ST end-to-end optical-based survey concept. For the detection of new debris, a network of wide field of view survey stations is considered: those stations are able to detect small objects and associated image processing (detection and tracking) allow a preliminary restitution of their orbit. Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/24/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx Proc. of SPIE Vol. 8186 81860F-7 Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/24/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx

The Automated Transfer Vehicle (ATV) is an ESA funded autonomous spacecraft designed and developed by several European aerospace companies as a European contribution to the International Space Station (ISS). Its function is fourfold: to supply the station with consumables (fuel, air, and water) and pressurized payload, to boost ISS to a higher orbit and to provide a waste disposal capability. An on -board software function entitled GNC Measurements System (GMS) is in charge of the measurements collection and conditioning for the navigation algorithms, specifically also the provision of measurements to estimate ATV attitude. This function relies on a Gyro Assembly (GYRA) and on Failure Detection and Isolation (FDI) algorithms. Matlab simulators (dedicated to ATV or presenting modular functionality) have been developed to check that the performances are ensured whatever the flight phase, the GYRA configuration and the failure mode. This paper presents the GMS architecture, focusing on the GYRA services. It describes an innovative approach for the GYRA consistency equations and shows simulation results to illustrate the trade-off analysis. The last part of the paper is dedicated to the presentation of the Matlab simulators developed to test the functionality's of the GYRA Functional Unit: the ATV GYRA FDI simulator and the Gyro&Accelero FDI Toolbox.