论文标题
在Murchison射线界观测站的FM频段中对空间和时间分辨的射频干扰的调查
A survey of spatially and temporally resolved radio frequency interference in the FM band at the Murchison Radio-astronomy Observatory
论文作者
论文摘要
我们介绍了低频平方千米阵列（SKA），Murchison Radio-Astronomy天文台（MRO）的未来射频干扰（RFI）的首次调查，这些调查均在时间和空间上分辨出RFI。该调查是在FM频段内以1 MHz频率范围进行的，旨在涵盖距MRO最接近，最强的FM发射器（位于杰拉尔顿（Geraldton），距离约300 km）。使用工程开发阵列的第二次迭代以全天空成像模式进行了大约三天的时间，我们找到了一系列RFI信号。我们能够将信号分类为：直接从发射机，从他们的地平面收到的信号；飞机的反射（占观察持续时间的约13％）；地球轨道物体的反射；以及流星电离径的反射。总共我们在两种极化中以7.92 s分辨率分析了33,994张图像，分辨率约为3.5度，检测到约四万RFI事件。在MRO环境中，RFI的详细分解将使未来的详细分析RFI对SKA的低无线电频率对关键科学的可能影响。
We present the first survey of radio frequency interference (RFI) at the future site of the low frequency Square Kilometre Array (SKA), the Murchison Radio-astronomy Observatory (MRO), that both temporally and spatially resolves the RFI. The survey is conducted in a 1 MHz frequency range within the FM band, designed to encompass the closest and strongest FM transmitters to the MRO (located in Geraldton, approximately 300 km distant). Conducted over approximately three days using the second iteration of the Engineering Development Array in an all-sky imaging mode, we find a range of RFI signals. We are able to categorise the signals into: those received directly from the transmitters, from their horizon locations; reflections from aircraft (occupying approximately 13% of the observation duration); reflections from objects in Earth orbit; and reflections from meteor ionisation trails. In total we analyse 33,994 images at 7.92 s time resolution in both polarisations with angular resolution of approximately 3.5 deg., detecting approximately forty thousand RFI events. This detailed breakdown of RFI in the MRO environment will enable future detailed analyses of the likely impacts of RFI on key science at low radio frequencies with the SKA.
