.+

平方公里阵列(SKA)是一种新的射电干涉望远镜，目前正在设计中，其科学目标广泛，从揭开暗能量和暗物质的奥秘，到研究地外生命。设计和建造SKA是一项雄心勃勃的国际事业，预算为15亿欧元。通过我们的研究，我们将开发从SKA记录的原始数据中恢复图像所需的新算法--这是一项巨大的计算任务--使SKA雄心勃勃的科学目标成为可能。射电天文学的新时代正在迅速来临。SKA的设计工作进展顺利，计划于2018年在南非和澳大利亚开工建设。此外，许多旨在开发和测试SKA核心技术的探路者望远镜现在开始上线。SKA将由数千个独立的望远镜组成，所有望远镜都通过一种名为孔径合成的技术共同作用。由此产生的望远镜阵列将合成一个巨大的望远镜，其有效尺寸为1平方公里，相当于大约200个足球场。像SKA这样的无线电干涉望远镜是由Ryle和Hewish在英国发明的，他们因其成就而于1974年获得诺贝尔奖。这些第一批射电望远镜只由几个单独的碟子组成。组成SKA的数千个单独的望远镜将产生巨大的大数据挑战，即使考虑到预计在未来几年计算方面的进步-SKA的预期数据速率预计将比目前全球互联网流量高出许多倍。此外，SKA将看到非常宽的视场，这使得望远镜的建模变得非常复杂，并极大地增加了进一步的计算要求。我们将开发新的算法来克服SKA巨大的大数据和广域成像挑战。为了做到这一点，我们将利用革命性的压缩传感新理论。压缩传感是一项开创性的新发展，对许多领域的数据采集具有广泛的影响。在无线电干涉测量学中，它表明可以从比先前认为的更少的原始数据望远镜测量中恢复高保真图像，或者，对于给定的原始数据测量集合，可以实现更高的图像重建保真度。我们将开发用于无线电干涉成像的新型压缩传感技术，结合计算效率高的算法来模拟广域设置。我们将采取一种变革性的方法，开发全新的算法，对射电干涉望远镜观测到的原始数据进行成像，而不是对传统的成像算法进行渐进式改进。我们将把我们的技术应用于最近建造的南非KAT-7望远镜的观测，这是SKA探路者望远镜之一。这将为将我们的技术整合到当前和未来射电望远镜的成像管道中铺平道路。通过克服大数据和广域成像挑战，我们将确保SKA充分发挥其潜力，使其雄心勃勃的科学目标成为可能，如果历史是一个准确的指南，许多我们还无法预测或理解的偶然科学进步。

The Square Kilometre Array (SKA) is a new radio interferometric telescope currently under design, with broad-ranging science goals from uncovering the mysteries of dark energy and dark matter, to the study of extra-terrestrial life. Designing and building the SKA is an ambitious international endeavour, with a budget of 1.5 billion Euros. Through our research we will develop the novel algorithms required to recover images from the raw data recorded by the SKA -- a tremendous computational task -- making the ambitious science goals of the SKA achievable. A new era of radio astronomy is approaching rapidly. The design of the SKA is well underway, with construction scheduled to begin in South Africa and Australia in 2018. Moreover, many pathfinder telescopes intended to develop and test the core technology of the SKA are starting to come online now. The SKA will be comprised of thousands of separate telescopes, all acting together through a technique called aperture synthesis. The resulting telescope array will synthesise one single massive telescope, with an effective size of one square kilometre, equivalent to approximately 200 football pitches. Radio interferometric telescopes like the SKA were invented in the UK by Ryle and Hewish, who won the Nobel Prize in 1974 for their achievements. These first radio telescopes consisted of just a handful of individual dishes. The thousands of individual telescopes making up the SKA will produce a tremendous big-data challenge, even taking into account the advances in computing expected over the coming years -- the anticipated data-rate of the SKA is expected to be many times greater than current world-wide internet traffic. Furthermore, the SKA will see a very wide field-of-view, which complicates the modelling of the telescope significantly and dramatically increases the computational requirements further still.We will develop novel algorithms to overcome the tremendous big-data and wide-field imaging challenges of the SKA. To do so, we will exploit the revolutionary new theory of compressive sensing. Compressive sensing is a ground-breaking new development that has wide-ranging implications for data acquisition in many fields. In radio interferometry, it suggests that high-fidelity images may be recovered from many fewer raw data telescope measurements than previously thought possible, or alternatively, that much higher image reconstruction fidelity can be achieved for a given set of raw data measurements. We will develop novel compressed sensing techniques for radio interferometric imaging, incorporating computationally efficient algorithms to model the wide-field setting. Rather than making incremental improvements to traditional imaging algorithms, we will take a transformative approach, developing radically new algorithms for imaging the raw data observed by radio interferometric telescopes. We will apply our techniques to observations made by the recently built South African KAT-7 telescope, one of the SKA pathfinder telescopes. This will pave the way towards the integration of our techniques into the imaging pipelines of current and future radio telescopes.By overcoming big-data and wide-field imaging challenges we will ensure that the SKA reaches its full potential, making possible its ambitious science goals and, if history is an accurate guide, many serendipitous scientific advances that we cannot yet predict or comprehended.