摘要
设计一种基于地震检波器的实验系统,分析地雷对地表声阻抗率的影响。用音响发射扫频的正弦声波穿透到地下土壤,用声级计和地震检波器分别测得地表声压级和振动速度。测试数据显示,没有地雷的地表声阻抗率与有地雷的比值在72,140Hz处出现2个极大值,用相长干涉原理和地雷与其上方土壤的谐振作用解释了这一现象。结果表明:地雷能在较宽频带内减小地面声阻抗率,所设计的实验系统可用于声波探雷的进一步研究。
A geophone-based experimental system is designed to analyze landmines＇ impact on earth surface acoustic impedance. Loudspeaker is used to insonify a swept sine tone over the soil. Sound level meter and geophone are respectively adopted to measure the applied acoustic pressure level and the induced vibration velocity at the surface. The experimental data shows that the ratio of surface acoustic impedance off-to-on mine appears two peak values at 72 Hz and 140 Hz. Constructive interference theory and resonance mechanism between the mine and the soil on top of its are used to explain such phenomenon. The results indicate that landmines decrease the surface acoustic impedance within a wider frequency range and the presented system can be used to further experimental study of acoustic landmines detection.
出处
《传感器与微系统》
CSCD
北大核心
2008年第8期36-38,41,共4页
Transducer and Microsystem Technologies
基金
总装备部国防预研基金资助项目(9140A09022101)
天津市自然科学基金重点资助项目(05YFJMJC14100)
关键词
声阻抗率
地雷探测
地震检波器
声压级
acoustic impedance
landmine detection
geophone
sound pressure level
