AI 中文总结
本文针对高海拔太赫兹太阳（HATS）望远镜采集系统，完成实验表征与电压-温度校准，对比六种窗函数的FFT与正弦曲线拟合方法，得出汉明窗精度最高，相关技术可拓展至多领域热探测。
AI 中文摘要
太赫兹波段在太阳天文学领域的探索尚不充分，主要受限于技术瓶颈。直到近期，才出现了少数新型望远镜，例如高海拔太赫兹太阳（HATS）光度计，开始对该光谱范围内的太阳活动进行监测。本文针对HATS采集系统开展实验表征与电压-温度校准工作。HATS采用高莱盒（Golay cell）捕获入射辐射，入射辐射由20Hz叉形斩波器进行调制；随后通过加窗函数和快速傅里叶变换（FFT），在预定时间间隔内获取信号幅值。为表征该采集系统，研究人员使用温度范围为100至500℃（即373.15K至648.15K）的黑体校准源作为太赫兹辐射源，对比了两种信号恢复方法：正弦曲线拟合，以及FFT结合六种窗函数（矩形窗、汉明窗、汉宁窗、巴特利特窗、布莱克曼窗、平顶窗）。定量结果表明，系统在输入源温度范围内的响应具有高度线性；其中汉明窗的精度最高，其均方根误差（RMSE）为15.48，校准温度-电压系数为10.32±0.13 mV/K；相比之下，巴特利特窗的误差最高，RMSE为16.02。窗函数的选择对校准系数的影响较小，校准系数范围为10.32至10.43 mV/K，均处于实验不确定度范围内。除太阳测光外，本文确立的信号调制与加窗概念还可广泛应用于其他需要高灵敏度热探测的领域，如高温制造的工业测温、大气水汽的环境监测，以及基于太赫兹辐射的非侵入式组织分析医学成像系统的开发。
英文摘要
The THz range has been under-explored for solar astronomy, mainly due to technological limitations. Only recently, a few new telescopes, such as the High Altitude Terahertz Solar (HATS) photometer, have been monitoring the solar activity in this range of the spectrum. This paper presents the experimental characterization and voltage-to-temperature calibration of the HATS acquisition system. HATS uses a Golay cell for capturing the incoming radiation, modulated by a 20 Hz fork chopper. The amplitude of the signal is then obtained at predetermined time intervals by applying a windowing function and an FFT to the signal. To characterize this acquisition system, a blackbody calibrator, with temperatures varying from 100 to 500 C (373.15 K to 648.15 K), was used as a THz source, and two signal recovery methodologies were compared: sinusoidal curve fitting and FFT combined with six windowing functions (rectangular, Hamming, Hann, Barlett, Blackman, and Flat Top). Our quantitative results demonstrate high linearity in the system's response over the input source's temperature range, with the Hamming window achieving the highest precision, yielding a Root Mean Square Error (RMSE) of 15.48 and a calibration temperature-to-voltage factor of 10.32 +- 0.13 mV/K. In contrast, the Bartlett window presented the highest error (RMSE 16.02). The choice of windowing function had only a minor effect on the calibration factors, which ranged from 10.32 to 10.43 mV/K, all within the experimental uncertainties. Beyond solar photometry, the signal modulation and windowing concepts established here are highly applicable to other fields requiring high-sensitivity thermal detection, such as industrial pyrometry for high-temperature manufacturing, environmental monitoring of atmospheric water vapor, and the development of medical imaging systems based on Terahertz radiation for non-invasive tissue analysis.
Comments15 pages, 5 figures, accepted for publication (SPIE Journal of Astronomical Telescopes, Instruments, and Systems)
