Collaborative Research: CubeSat-based Ground-to-Space Bistatic Radar Experiment--Radio Aurora Explorer

该项目是SRI国际空间科学首席研究员和密歇根大学工程学首席研究员之间的合作。这项为期三年的跨学科团队工作的目标是建造和操作一个微小的、所谓的立方体卫星航天器，携带超高频雷达接收器有效载荷。这颗卫星的发射将作为国防部定于2009年12月发射的次要任务。该卫星将与地面的阿米西里非相干散射雷达协调运行，以调查高纬度电离层中场向不规则产生的射电极光。射电极光探测器飞行任务的主要科学目标是了解导致极低电离层(80-300公里)电子密度场向不规则的等离子体不稳定性的微观物理。RAE任务是专门设计用来以极高的角分辨率(~0.5度)遥测~1m尺度FAI随高度变化的波谱，特别是测量不规则性的磁场排列。由于高纬度的磁场几何形状，这种双基地(地面雷达对卫星)配置是执行这些测量的唯一方式，在这种配置中，一个狭窄的雷达束从FAI散布，然后由CubeSat接收器观测。更好地了解电离层不规则性及其在电离层动力学中的作用是一项重要的空间气象研究目标，因为电离层中的等离子体结构可能对通过卫星、高频和甚高频无线电进行的通信产生不利影响，并对导航、跟踪和定位产生不利影响。该项目具有非常强大的教育成分；它依赖于本科生和研究生在使命的各个方面的广泛参与。立方体卫星任务中涉及的新的、基本上未经验证的技术，本质上使该项目与重大风险联系在一起。然而，另一方面，该项目不仅在其自身的研究领域内，而且在更大的空间科学和大气研究领域，以及在航空航天工程和教育领域，都具有巨大的变革潜力。

This project is a collaboration between a space science Principal Investigator (PI) at SRI International and an engineering PI at University of Michigan. The objective of this three-year cross-disciplinary team effort is to build and operate a tiny, so-called CubeSat, spacecraft carrying a UHF radar receiver payload. Launch of the satellite will be as a secondary on a Department of Defense launch scheduled for December 2009. The satellite will be operated in coordination with the AMISR incoherent scatter radar from the ground to investigate the radio aurora from field-aligned irregularities in the high-latitude ionosphere. The primary scientific objective of the Radio Aurora Explorer (RAE) mission is to understand the microphysics of plasma instabilities that lead to field-aligned irregularities (FAI) of electron density in the polar lower (80-300 km) ionosphere. The RAE mission is specifically designed to remotely measure, with extremely high angular resolution (~0.5 degree), the wave spectrum of ~1 m scale FAI as a function of altitude, in particular measuring the magnetic field alignment of the irregularities. Due to the magnetic field geometry at high latitudes this bi-static (ground radar to satellite) configuration, in which a narrow radar beam is scattered off the FAI and then observed by the CubeSat receiver, is the only way to perform these measurements. Better understanding of ionospheric irregularities and their role in ionospheric dynamics is an important space weather research objective because plasma structures in the ionosphere can have an adverse effect on communications via satellite, HF and VHF radio and as well as an adverse effect on navigation, tracking, and positioning. The project has a very strong educational component; it relies on extensive undergraduate and graduate student involvement through all aspects of the mission. The new, largely unproven technology involved in cubesat missions, inherently makes the project associated with significant risks. On the other hand, however, the project has tremendous potential to be transformational not only within its own research area but also for the larger field of space science and atmospheric research as well as within aerospace engineering and education.