DE 1 VLF observations during activity wave injection experiments
DE 1 VLF observations during activity wave injection experiments
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活动波注入实验期间的 DE 1 VLF 观测
DOI：
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发表时间：
1994
期刊：
影响因子：
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通讯作者：
J. L. Green
中科院分区：
文献类型：
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作者：
V. Sonwalkar;U. Inan;T. Bell;R. Helliwell;O. Molchanov;J. L. Green
我们报告了协调的高空卫星观测，以支持第一个空基甚低频（VLF）波注入实验之一，即苏联Aktivny使命。Aktivny卫星（A）的设计目的是携带一个甚低频发射机（标称频率约为10千赫，发射机功率约为10千瓦），该发射机与近极轨道（倾角83度，远地点约为2，500公里，近地点约为500公里）上的一个直径为20米的环形天线相连。我们把注意力集中在Aktivny和DE 1卫星之间的连接实验。由于环形天线的部署问题，天线的辐射功率能力大大降低。虽然这大大降低了在卫星上接收可检测信号电平的期望，但DE 1/Aktivny会合实验仍然作为可能对辐射功率设置上限的一种手段进行。在1989年11月至1990年4月期间，共进行了10次DE 1/Aktivny波注射。在每个会话期间，Aktivny发射器以10.537 kHz以1 s开-1 s关格式操作，持续以会合时间为中心的6分钟。在三个会合期间（1989年12月12日、26日和27日），DE 1和Aktivny都在南半球，DE 1的高度相对较低（从6211到14，810公里），因此根据上面开发的射线追踪标准，提供了最佳的会合可能性。在大多数日子里，欧米茄发射机信号以及常见的自然波现象，如哨声（0（+））和嘶嘶声，都清楚地看到远高于背景水平，但没有证据表明Aktivny 1 s On/ 1 s Off模式。虽然DE 1卫星上的LWR没有检测到Aktivny信号，但实验约束允许我们对Aktivny发射机在哨声模式下辐射的总功率设置上限。使用实验参数，和0.05 μ V/m的LWR的最小可检测信号电平，我们发现Aktivny卫星在哨声模式下辐射的总功率的上限约为10 mW。对未来的天基波注入实验提出了几点建议。
We report on coordinated high-altitude satellite observations in support of one of the first space-based very low frequency (VLF) wave injection experiments, namely the USSR Aktivny mission. The Aktivny satellite (A) was designed to carry a VLF transmitter (nominal frequency approximately 10 kHz, transmitter power approximately 10 kW) coupled to a 20-m-diameter loop antenna in a nearly polar orbit (83 deg inclination, apogee approximately 2500 km, perigee approximately 500 km). We focus our attention on conjunction experiments between the Aktivny and DE 1 satellites. Because of problems in the deployment of the loop antenna, the radiated power capability of the antenna was significantly reduced. Although this substantially reduced the expectation of receiving detectable signal levels on the satellite, the DE 1/Aktivny conjunction experiments were nevertheless carried out as a means of possibly placing an upper limit on the radiated power. During the period November 1989 through April 1990, a total of 10 DE 1/Aktivny wave injection sessions were conducted. During each session the Aktivny transmitter operated at 10.537 kHz with 1 s On - 1 s Off format, for a period of 6 min centered around the conjunction time. During three conjunction periods (December 12, 26, and 27, 1989) both DE 1 and Aktivny were in the southern hemisphere, and DE 1 was at relatively low altitudes (ranging from 6211 to 14,810 km), thus providing the best conjunction possibilities according to the ray tracing criteria developed above. On most days, Omega transmitter signals as well as commonly occuring natural wave phenomena such as whistlers (0(+)) and hiss were clearly seen well above the background level, but there was no evidence of the Aktivny 1 s On/ 1 s Off pattern. Though no Aktivny signals were detected by the LWR on the DE 1 satellite, the experimental constraints allow us to place an upper limit on the total power radiated by the Aktivny transmitter in the whistler-mode. Using experimental parameters, and the minimum detectable signal level of 0.05 muV/m for LWR, we find the upper limit on the total power radiated by the Aktivny satellite in the whistler-mode to be approximately 10 mW. Several recommendations for future space-based wave injection experiments are presented.