面向空间引力波探测的惯性传感器噪声分析和敏感探头热控制研究

The space-borne Gravitational Wave (GW) detection, compared to ground-based detection, aims at more universe sources, which can last much longer time, so that the signals contain more useful astronomical information. The inertial sensor, as one of the key payloads for LISA, TianQin and DECIGO missions and so on, needs a aceleration noise level of or even better than 10-15m/s2/Hz1/2, which is at least three orders stricter than the noise level of best space-qualified inertial sensor - the GOCE sensor. To suppress noise from different types of sources, it is essential to understand the active mechanism of the noises, to model the noises and then to define the requirements to the application environment, for instance for LISA the sensor head needs a thermal stability environment of about 10-5K/Hz1/2. Aiming at the inertial sensor needed for the proposed space GW detection mission of China, this study will focus on defining the needed features of the sensor head, modeling all the dangerous parasitic and coupling noises, clarifying the requirement of the inertial sensor to its work surrounding. Based on the theoretical analyses, a high-stable thermal control system will be also developed to be able to suppress the thermal-related noise arising from the sensor head. This study is expected to stimulate the development of the super-high-precision inertial sensor, as well as the proposed space GW mission of China.

空间引力波探测相对地面引力波探测而言，其目标波源多、效应的持续时间长、因而信号包含更丰富的天文信息，是地面引力波探测的必然延续。LISA、TianQin、DECIGO等空间引力波探测计划要求惯性传感器的加速度噪声达到甚至优于10-15m/s2/Hz1/2，比当前已经实验检验的GOCE的惯性传感器还要高三个量级以上，为地面研制带来了极大挑战。为了抑制各类噪声，需要分析各类噪声的作用机制、建立误差模型并明确对环境稳定性的需求指标，例如LISA探头的温度稳定度需达到10-5K/Hz1/2的严苛要求。本课题拟针对我国自主的空间引力波探测计划所需的惯性传感器，首先确定探头的主要结构特征，对其主要的寄生和耦合噪声源进行系统的建模和误差分配，提出对敏感探头热控制水平的需求指标；在此基础上实验研究敏感探头的超高精度热控制系统，以促进我国在高精度空间惯性传感器、空间引力波探测这一尖端科技领域的发展。

空间引力波探测相对地面引力波探测而言，其目标波源多、效应的持续时间长、因而信号包含更丰富的天文信息，是地面引力波探测的必然延续。LISA、TianQin、DECIGO等空间引力波探测计划要求惯性传感器的加速度噪声达到甚至优于10-15m/s2/Hz1/2，比当前得到验证的GOCE惯性传感器的噪声还低三个量级，为地面的预先研制带来了极大的挑战。本课题针对我国自主的空间引力波探测计划所需的惯性传感器展开研究，目前取得的进展包括：（1）已完成惯性传感器探头结构特征的主要论证工作；（2）进行了惯性传感器的理论建模和误差分解；（3）设计和建设了一个高精度环境试验系统，为地面的噪声试验做准备；（4）完成了基于电桥和频率调制的高精度温度传感器的初步研制，温度测量范围15-35oC，测量噪声在1mHz处优于5×10-5 oC/Hz1/2。研制的二级主动温度控制系统，温度波动抑制系数在1mHz附近达到25000倍。相关研究对促进我国空间引力波探测惯性传感器的发展具有显著意义。