Hyperspectral imaging is an important technique in remote sensing which is characterized by high spectral resolutions. With the advent of new hyperspectral remote sensing missions and their increased temporal resolutions, the availability and dimensionality of hyperspectral data is continuously increasing. This demands fast processing solutions that can be used to compress and/or interpret hyperspectral data on board spacecraft imaging platforms in order to reduce downlink connection requirements and perform a more efficient exploitation of hyperspectral data sets in various applications. Over the last few years, reconfigurable hardware solutions such as field programmable gate arrays (FPGAs) have been consolidated as the standard choice for on-board remote sensing processing due to their smaller size, weight and power consumption when compared with other high performance computing systems, as well as to the availability of more FPGAs with increased tolerance to ionizing radiation in space. Although there have been many literature sources on the use of FPGAs in remote sensing in general and in hyperspectral remote sensing in particular, there is no specific reference discussing the state-of-the-art and future trends of applying this flexible and dynamic technology to such missions. In this work, a necessary first step in this direction is taken by providing an extensive review and discussion of the (current and future) capabilities of reconfigurable hardware and FPGAs in the context of hyperspectral remote sensing missions.

Abstract-New generation embedded systems demand high performance, efficiency and flexibility. Reconfigurable hardware can provide all these features. However the costly reconfiguration process and the lack of management support have prevented a broader use of these resources. To solve these issues we have developed a scheduler that deals with task-graphs at run-time, steering its execution in the reconfigurable resources while carrying out both prefetch and replacement techniques that cooperate to hide most of the reconfiguration delays. In our scheduling environment task-graphs are analyzed at design-time to extract useful information. This information is used at run-time to obtain near-optimal schedules, escaping from local-optimum decisions, while only carrying out simple computations. Moreover, we have developed a hardware implementation of the scheduler that applies all the optimization techniques while introducing a delay of only a few clock cycles. In the experiments our scheduler clearly outperforms conventional run-time schedulers based on As-Soon-As-Possible techniques. In addition, our replacement policy, specially designed for reconfigurable systems, achieves almost optimal results both regarding reuse and performance.

The Variscan Montes de Toledo Batholith (MTB) is an E-W linear array of peraluminous granite plutons which is chemically segmented. The study is focused on the western segment of the MTB (W-MTB), mainly composed of granites with slightly lower CaO and higher P₂O₅ contents than associated eastern plutonic units and nearby S-type granites, giving them a more pronounced peraluminous nature. The chemical contrast is also observed in isotopic composition, especially in radiogenic Nd and Pb ratios. The W-MTB granites have higher initial ε_Nd (-5.0 to -5.9) and lower ²⁰⁶Pb/²⁰⁴Pb and ²⁰⁸Pb/²⁰⁴Pb ratios than peraluminous types from the E-MTB segment. A mixed pelitic-greywackeous derivation from regional Neoproterozoic formations is suggested whereas lower crustal and meta-igneous sources were involved in the origin of the easternmost MTB granites. The presence of igneous muscovite together with coexisting andalusite and sillimanite in some of the studied granites suggests that solidus was reached at 650-700 °C and depth corresponding to the pressure of 2-3 kbar

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