In this paper, we present the CubeSat version of a scientific instrument called the multi-Needle Langmuir Probe (m-NLP). The m-NLP instrument measures the electron density in the ionosphere with kHz sampling rate, yielding meter scale resolution on low Earth orbit satellites. The sounding rocket version of m-NLP has flight heritage from nine sounding rockets. However, to get an in-orbit demonstration of the system a CubeSat implementation has been developed. The m-NLP measurement principle is based on several fixed bias probes, where each probe has to be biased above the spacecraft potential. To ensure that this requirement is fulfilled, the CubeSat version of the m-NLP will feature a new miniaturized thermionic electron emitter, which can actively control the potential of the satellite. The emitter is designed to accommodate the low size, weight, and power challenges of the CubeSat platform. Together with the in-flight determination of the spacecraft floating potential, it can autonomously control the potential of the spacecraft by emitting electrons. Preliminary, test results from the plasma chamber at the European Space and Technology Center in Holland are shown, verifying that a miniaturized electron emitter is able to actively control the floating potential of the spacecraft and, hence, improve the accuracy of the electron density measurements.

中文翻译：

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多针朗缪尔探针系统，用于立方体卫星上的电子密度测量和主动航天器电位控制

在本文中，我们介绍了一种名为多针朗缪尔探测器 (m-NLP) 的科学仪器的 CubeSat 版本。m-NLP 仪器以 kHz 采样率测量电离层中的电子密度，在低地球轨道卫星上产生米级分辨率。m-NLP 的探空火箭版本具有九个探空火箭的飞行传统。然而，为了获得该系统的在轨演示，已经开发了 CubeSat 实现。m-NLP 测量原理基于几个固定偏置探头，其中每个探头必须偏置在航天器电位以上。为确保满足这一要求，CubeSat 版本的 m-NLP 将配备一个新的小型化热电子发射器，可以主动控制卫星的电位。发射器旨在适应低尺寸、重量、CubeSat 平台的电源挑战。结合在飞行中确定航天器浮动电位，它可以通过发射电子自主控制航天器的电位。初步展示了荷兰欧洲空间与技术中心等离子体室的测试结果，验证了小型化电子发射器能够主动控制航天器的浮动电位，从而提高电子密度测量的准确性。