摘要
针对生化光电等领域弱信号检测的需要以及窄带滤波器抑制噪声能力的不足,设计了一种通用型弱电压检测与恢复系统。系统基于锁相放大原理,选用级联的平衡调制解调器件AD630对弱信号进行调制与解调恢复;并通过Labview驱动声卡产生白噪声来调节弱信号的信噪比。实验证明系统对信噪比接近-40dB的10μV弱信号有较好的检测恢复能力,检测增益接近30dB,并且具有进一步提高性能指标的潜力与空间。
A multipurpose weak signal detection and recovery system is designed to satisfy the requirement of weak signal detection in biochemistry and photoelectricity,and solve the deficiency of noise limiting of narrowband filter.Based on lock-in amplifying princi- ple,the system uses cascade Modulator/Demodulator AD630 to modulate and demodulate weak signals, and modify SNR by the white noise generating from soundcard driven via Labview.The experiment results show the proposed system has better detection and recovery capability for 10 μV weak signal with SNR approximately -40 dB, and the gain of detection is close to 30 dB, and in addition,it has potential for improving its performance specifications.
出处
《无线电通信技术》
2015年第3期86-88,92,共4页
Radio Communications Technology
基金
安徽省高等学校省级自然科学研究项目(KJ2013Z094)
安徽师范大学青年教师科研专项资助基金(160721340)
