西南科技大学 信息工程学院, 四川 绵阳 621010
针对石英增强光声检测系统中石英音叉共振信号的特征及提取要求, 设计了一款六阶切比雪夫有源模拟带通滤波器。根据切比雪夫滤波器理论和Sallen-Key拓扑结构模型完成实际电路的设计, 并通过石英音叉共振特性测试实验对滤波器的性能做出了验证。实验结果表明, 该滤波器能对石英音叉光声信号进行滤波去噪并无失真放大, 其性能指标满足: 通频带宽935 Hz, 波纹0.8 dB, 带外衰减51 dB, 品质因数(Q)值35.09, 能有效抑制环境噪声, 可用于石英增强光声光谱检测领域光声前端信号的处理。
光声检测 石英音叉 带通滤波器 共振特性 带外衰减 photoacoustic detection quartz tuning fork bandpass filter resonance characteristic out-of-band attenuation
Shuang Wang 1,2,3,*Jie Zhou 1,2,3Junfeng Jiang 1,2,3,**Kun Liu 1,2,3[ ... ]Tiegen Liu 1,2,3
Author Affiliations
Abstract
1 School of Precision Instrument and Opto-electronics Engineering, Tianjin University, Tianjin 300072, China
2 Key Laboratory of Opto-electronics Information Technology, Ministry of Education, Tianjin 300072, China
3 Tianjin Optical Fiber Sensing Engineering Center, Institute of Optical Fiber Sensing of Tianjin University, Tianjin 300072, China
A multi-channel synchronous demodulation system of a polarized low-coherence interferometer (PLCI) based on a matrix charge-coupled-device (CCD) is proposed and demonstrated. By using special designs, the system allows the signals from different channels to be received and demodulated synchronously. Multichannel air pressure experiments were implemented to verify the effectiveness of the proposed system. The experiment results showed that the Fabry–Perot (F–P) sensors could be demodulated synchronously with a high tolerance for light sources and sensors, which indicated that any sensor and light source that can be demodulated by PLCI were allowed to be employed, leading to a wide application in the field of multichannel synchronous measurement.
multi-channel synchronous demodulation polarized low-coherence interferometer matrix charge-coupled-device Fabry–Perot sensors Chinese Optics Letters
2020, 18(7): 071202
