Square Kilometer Array Design (SKADS)

平方公里阵列设计 (SKADS)

• 批准号: PP/E000231/1
• 负责人: Peter Wilkinson
• 金额: $ 341万
• 依托单位: University of Manchester
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2006
• 资助国家: 英国
• 起止时间: 2006 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=PP%2FE000231%2F1
• 关键词: Square; Kilometer; Array; Design; SKADS

The 'Square Kilometre Array' (SKA) will be an international radio telescope with a collecting area of one million square metres - equivalent to about 200 football pitches / making SKA 200 times bigger than the University of Manchester's Lovell Telescope at Jodrell Bank. The four-year Square Kilometre Array Design Study, SKADS, brings together European and international astronomers to formulate and agree the most effective design. The final design will enable the SKA to probe the cosmos in unprecedented detail, answering fundamental questions about the Universe, such as 'what is dark energy?' and 'how did the structure we see in galaxies today actually form?' The SKA concept was first proposed to observe the characteristic radio emission from hydrogen gas. Measurements of the hydrogen signature will enable astronomers to locate and weigh a billion galaxies It will also test Einstein's General Theory of Relativity to the limit / and perhaps prove it wrong. It will add to the long list of fundamental discoveries made by radio astronomers including quasars, pulsars and the radiation from the Big Bang. The design will be complete by 2010 and building SKA with full operation in 2020. Another target for the SKA is pulsars; spinning remnants of stellar explosions which are the most accurate clocks in the universe. A million times the mass of the Earth but only the size of a large city, pulsars can spin around hundreds of times per second. With the SKA we will find a pulsar orbiting a black hole and, by watching how the clock rate varies, we can tell if Einstein had the last word on gravity or not. The scale of the instrument needed to fulfil these science goals is huge, a total of 1,000,000 square metres of collecting area spread across a continent, but the technology required to fulfil the potential of the instrument is in many ways more daunting. The SKADS effort is based on phased array receivers. When placed at the focus of conventional mass-produced radio 'dishes', these arrays operate like wide-angle radio cameras observing huge areas of sky. A separate, much larger, phased array at the centre of the SKA constantly scans the sky. Catalyst funding has been provided by the European Commission of 27% of the total of ¤38M funding over the next four years. The UK has invested £5.6M (¤8.3M) funding provided by PPARC. The UK's is contributing 30% of the SKADS programme. The UK is concentrating on sophisticated digital phased arrays and the distribution and analysis of the enormous volumes of data which the SKA will produce. The main technological design aim of UK SKADS is to produce a dual polarisation all-digital phased array 'tile' approximately 1m by 1m, so call '2-PAD'. This will represent the culmination of a number of fundamental system design studies into array antenna element design; very low cost semiconductors for the critical low noise amplifiers (LNAs) at the antenna and the very high speed analogue to digital converters (ADCs) which put the received signal into the digital domain; considerable research into very high speed digital processing techniques which are affordable in terms of cost and power and the reduction of interference both external and self-induced by the equipment. This development is expected to be the highest performance phased array tile for astronomical purposes available at the end of the project. The requirements and performance of a simulated SKA will be investigated when used for selected astronomical observations. The results will be key to deriving the target specification for the SKA and will be used extensively by the engineering groups. The communication and computing resources of a completed SKA will be simulated in order to find the optimal configurations. Techniques for distributing very accurate time signals will be worked upon and demonstrated. This is vital to a radio telescope using many receiving systems sometimes separated by thousands of kilometres.

“平方公里阵列”（SKA）将是一个国际射电望远镜，其收集面积为100万平方米-相当于约200个足球场/使SKA比曼彻斯特大学的洛弗尔望远镜大200倍。为期四年的平方公里阵列设计研究（SKADS）汇集了欧洲和国际天文学家，制定并商定最有效的设计。最终的设计将使SKA能够以前所未有的细节探测宇宙，回答关于宇宙的基本问题，例如“什么是暗能量？”以及我们今天在星系中看到的结构是如何形成的？SKA概念最初是为了观察氢气的特征无线电发射而提出的。对氢信号的测量将使天文学家能够定位和称量10亿个星系的重量，这也将考验爱因斯坦的广义相对论的极限，也许会证明它是错误的。它将为射电天文学家的一长串基本发现增添新的发现，包括类星体、类星体和宇宙大爆炸的辐射。该设计将于2010年完成，并于2020年建成SKA并全面运营。SKA的另一个目标是恒星爆炸的旋转残骸，这是宇宙中最精确的时钟。质量是地球的一百万倍，但只有一个大城市的大小，火星每秒可以旋转数百次。有了SKA，我们将发现一颗围绕黑洞运行的脉冲星，通过观察时钟频率的变化，我们可以判断爱因斯坦是否对引力有最后的看法。实现这些科学目标所需的仪器规模是巨大的，总共有1，000，000平方米的收集面积遍布整个大陆，但实现仪器潜力所需的技术在许多方面更加艰巨。SKADS的工作是基于相控阵接收机。当放置在传统的大规模生产的无线电“碟”的焦点时，这些阵列就像广角无线电摄像机一样观察大片天空。SKA中心有一个单独的、大得多的相控阵，不断扫描天空。欧盟委员会在未来四年提供了3800万欧元资金总额的27%。英国已投入PPARC提供的560万英镑（830万英镑）资金。英国将为SKADS项目贡献30%的资金。联合王国正集中精力研究复杂的数字相控阵，以及SKA将产生的大量数据的分发和分析。英国SKADS的主要技术设计目标是生产一个大约1米乘1米的双极化全数字相控阵“瓦”，所以称为“2-PAD”。这将代表对阵列天线元件设计的一些基本系统设计研究的高潮;用于天线处的关键低噪声放大器（LNA）和将接收信号置于数字域的非常高速的模数转换器（ADC）的非常低成本的半导体;大量研究非常高速的数字处理技术，这些技术在成本和功率方面是负担得起的，并且减少了外部和自身的干扰，由设备引起的。这一发展预计将是最高性能的相控阵瓦天文目的提供在该项目结束。将研究模拟SKA用于选定天文观测时的要求和性能。这些结果将是推导SKA目标规格的关键，并将被工程组广泛使用。完成SKA的通信和计算资源将被模拟，以找到最佳的配置。将研究和演示分发非常精确的时间信号的技术。这对于使用许多接收系统的射电望远镜来说是至关重要的，有时这些接收系统相隔数千公里。