【作者】 朱虹； 林君； 王智宏； 占细雄；

【Author】 Zhu Hong Lin Jun Wang Zhihong Zhan Xixiong (Institute of Intelligent Instruments and Measurement Technology, Jilin University, Changchun 130026)

【机构】 吉林大学智能仪器与测控技术研究所；

【摘要】 根据仪器用于野外,环境恶劣、工作电压不稳定及近红外光谱信号的特点,对传统的锁定放大电路进行改进,设计了实用的参考信号频率自调整的锁定放大电路,采用锁相技术使参考信号频率自调整保持与被测信号频率相位一致,并采用同步累积技术进一步提高信噪比,从而精确地从噪声中提取出光谱信号,达到了良好效果。更多还原

【Abstract】 According to the bad conditions in which the field instrument was used and the characteristics of NIRS, improves the traditional locked-in amplifier and designs a new one whose reference signal’s frequency can be adjusted to the signal’s automatically. The ratio of signal to noise (SNR) is greatly improved through synchronous cumulating method. So the spectrum signal is acquired from the strong noise accurately.更多还原