A VLF Beacon Transmitter at South Pole

0093381Inan 拟议的工作是为期三年的努力，在南极建立和运行甚低频（VLF）信标发射机，用于连续测量太阳对地球中层和低电离层的影响。 具体来说，发射机将产生有关太阳质子事件、来自地球外辐射带的相对论（300 keV）电子沉淀以及高纬度/极冠磁层-电离层耦合过程的高能电子沉淀和焦耳加热成分的数据。在地球同步轨道上测量的相对论电子数量表现出与亚暴和太阳活动相关的显着波动。 在事件发生期间，这些高能电子可以渗透到低至 30-40 公里的高度，产生电离、X 射线，并可能影响涉及臭氧生成的化学反应。 将通过各个南极站接收到的南极甚低频信号的幅度和相位变化来观测相对论电子降水的程度。南极信标将协同加强其他南极高层大气研究工作，例如自动地球物理观测站计划和南半球相干高频雷达网络（SUPERDARN）。拟议的计划还有力地补充了正在进行的基于卫星的低海拔（SAMPEX）和高海拔（POLAR）捕获和沉淀高能电子的测量。 信标将以大约 20 kHz 的频率进行传输，通过约 6.25 公里（尖端到尖端长度）长的水平偶极天线辐射 1 kW 的总功率。它将在计算机控制下运行，天气时间表为每 15 分钟约 1 分钟一次。***

0093381InanThe proposed work is a three year effort to establish and operate a very low frequency (VLF) beacon transmitter at South Pole, for the continuous measurement of solar effects on the Earth's mesosphere and lower ionosphere. Specifically the transmitter will produce data on solar proton events, relativistic (300 keV) electron precipitation from the Earth's outer radiation belts, and energetic electron precipitation and Joule heating components of high latitude/polar cap magnetosphere-ionosphere coupling processes. The relativistic electron population as measured at geosynchronous orbit exhibits pronounced fluctuations in association with substorm and solar activity. During an event, these highly energetic electrons can penetrate to altitudes as low as 30-40 km, producing ionization, x-rays and possibly affecting chemical reactions involving ozone production. The extent of relativistic electron precipitation will be observed by means of amplitude and phase variations of the South Pole VLF signal as received at various Antarctic stations. The South Pole beacon will synergistically enhance other antarctic upper atmospheric research efforts, such as the Automatic Geophysical Observatory programs and the southern hemisphere coherent HF radar network (SUPERDARN). The proposed program also strongly complements ongoing satellite based measurements of trapped and precipitating high energy electrons both at low altitudes (SAMPEX) and high altitudes (POLAR). The beacon will transmit at approximately 20 kHz, radiating 1 kW of total power with a ~6.25 km (tip-to-tip length) long horizontal dipole antenna. It will be operating under computer control with a synoptic schedule of about 1 min out of every 15 minutes.***