Strategies for Co-existence of Radio Telescope Arrays with Broadcast Stations and Wireless Communication Systems

加强无线电频谱接入（enhanced Access to Radio Spectrum）计划是根据2010年《关于启动无线宽带革命的总统备忘录》设立的，该备忘录是国会授权的国家宽带计划的一部分。它在2010年国情咨文和后来的2012年中产阶级税收减免和创造就业法案（超过三分之一的法案涉及无线电频谱），PCAST 2012年报告[总统科学技术顾问委员会]（呼吁大幅增加频谱共享的使用）和2013年总统备忘录（扩大美国在无线创新方面的领导地位）中被引用。该项目的目的是确定大胆的新概念，这些概念有可能有助于显著提高无线电频谱利用效率，保护无源传感服务，并使传统上服务不足的美国人从当前和未来的无线产品和服务中受益。这对国家经济的影响很大，正如2015年初FCC以超过450亿美元的价格竞标65MHz频谱所看到的那样。它将使科学、工程、工业、民用和军事用户能够使用射频（RF）频谱。由于技术革新，如4G移动服务，以及无线互联网的快速增长，对无线宽带的需求激增。这一需求将需要利用传统上为射电望远镜指定的带宽以上的频率。这种频率侵犯可能会干扰天文数据的接收和解释，并因此损害对地外智慧的搜索和发现。该项目提出了无线用户对天文观测干扰最小的共存策略。该项目旨在通过开发干扰缓解技术来实现共存战略，这些技术考虑到望远镜观测方向的高仰角与基站和无线系统发射的信号的低仰角。共存战略要求授权的广播电台和无线发射机与射电望远镜合作，报告其位置并提供其信号结构的特性。干扰定位的先验知识简化了多单元望远镜阵列对干扰的消去。另一方面，天文事件与数字通信信号特征的区别使得有效的合作和非合作干扰识别和抑制成为可能。该项目有可能推进频谱共享和利用，从而增强美国工业界和学术机构在这一研发领域的未来能力。

This EARS (Enhancing Access to the Radio Spectrum) program was founded in response to the 2010 Presidential Memorandum on Unleashing the Wireless Broadband Revolution mandated by Congress as part of the National Broadband Plan. It was referenced in 2010 State of the Union and later on the Middle Class Tax Relief and Job Creation Act of 2012 (More than 1/3 of the bill deals with radio spectrum), the PCAST 2012 Report [President's Council of Advisors on Science and Technology] (which calls for vastly increased use of spectrum sharing) and the 2013 Presidential memo (Expanding America's Leadership in Wireless Innovation). The aim of this program is to identify bold new concepts with the potential to contribute to significant improvements in the efficiency of radio spectrum utilization, protection of passive sensing services, and in the ability for traditionally underserved Americans to benefit from current and future wireless-enabled goods and services. The impact is large on the economics of the Nation as seen on the last FCC bidding of 65MHz of the spectrum for over $45 billion early in 2015. It will enable access to science, engineering, industry, civilian and military users of the radio frequency (RF) spectrum.Demand for wireless broadband has soared due to technological innovation, such as 4G mobile services, and the rapid increase in wireless internet. This demand would require the utilization of frequencies over a bandwidth that has been traditionally slated for radio telescopes. This frequency infringement may interfere with reception and interpretation of astronomical data and, as such, compromise the search and discoveries of extraterrestrial intelligence. The project puts forward coexistence strategies where wireless users cause minimum interference to astronomical observations. The project aims at achieving the coexistence strategies by developing interference mitigation techniques that factor in the high-elevation of the look direction of the telescope compared to low-elevation angles of signals emitted by base-stations and wireless systems. A co-existence strategy calls for authorized broadcast stations and wireless transmitters to cooperate with radio telescopes by reporting their locations and providing properties of their signal structures. Prior knowledge of interference location simplifies its nulling and removal by telescope array of multiple units. On the other hand, the distinction in signal characteristics between astronomical events and those of digital communications enables effective cooperative as well as non-cooperative interference identification and suppression. The project has the potential to advance spectrum sharing and utilization and therefore enhance the future capacity for U.S. industry and academic institutions in this area of research and development.