针对当前对MEMS矢量水听器高可靠性迫切要求,设计了2×2单片集成四元阵列式MEMS矢量水听器,以保证其中一个敏感微结构失效损坏或工作不正常时,水听器仍能正常工作。结合ANSYS软件对阵列敏感微结构进行了仿真分析;设计了该微结构的...针对当前对MEMS矢量水听器高可靠性迫切要求,设计了2×2单片集成四元阵列式MEMS矢量水听器,以保证其中一个敏感微结构失效损坏或工作不正常时,水听器仍能正常工作。结合ANSYS软件对阵列敏感微结构进行了仿真分析;设计了该微结构的加工工艺流程;最后,对阵列式MEMS矢量水听器进行水声校准测试。测试结果表明:阵列式水听器可靠性明显提高,灵敏度达到-179 d B(0 d B=1V/μPa),具有良好的"8"字指向性。展开更多
针对传统波达方向(Direction of arrival,DOA)估计算法在小快拍数、低信噪比以及信源信号相干等条件下估计精度低等问题,提出一种基于迂回式匹配追踪算法的DOA估计方法.通过对空间按照潜在的入射角等角度进行划分,构造超完备冗余字典,...针对传统波达方向(Direction of arrival,DOA)估计算法在小快拍数、低信噪比以及信源信号相干等条件下估计精度低等问题,提出一种基于迂回式匹配追踪算法的DOA估计方法.通过对空间按照潜在的入射角等角度进行划分,构造超完备冗余字典,采用迂回式匹配追踪算法对稀疏信号进行重构,得到信号中的非零元素按位置编号转化成对应的方向角度,即正确的DOA估计值.仿真结果表明:基于迂回式匹配追踪算法的DOA估计算法在单快拍情况下仍能得到有效估计值,在强噪声环境中也具有较好的稳健性.展开更多
One-step patch near-field acoustical holography(PNAH) is a powerful tool for identifying noise sources from the partially known sound pressure field.The acoustical property to be reconstructed on the surface of intere...One-step patch near-field acoustical holography(PNAH) is a powerful tool for identifying noise sources from the partially known sound pressure field.The acoustical property to be reconstructed on the surface of interest is related to the partially measured pressure on the hologram surface in terms of sampling and bandlimiting matrices,which cost more in computation.A one-step procedure based on measuring of the normal component of the particle velocity is described,including the mathematical formulation.The numerical simulation shows that one-step PNAH based on particle velocity can obtain more accurately reconstructed results and it is also less sensitive to noise than the method based on pressure.These findings are confirmed by an underwater near-field acoustical holography experiment conducted with a vector hydrophone array.The experimental results have illustrated the high performance of one-step PNAH based on particle velocity in the reconstruction of sound field and the advantages of a vector hydrophone array in an underwater near-field measurement.展开更多
文摘针对当前对MEMS矢量水听器高可靠性迫切要求,设计了2×2单片集成四元阵列式MEMS矢量水听器,以保证其中一个敏感微结构失效损坏或工作不正常时,水听器仍能正常工作。结合ANSYS软件对阵列敏感微结构进行了仿真分析;设计了该微结构的加工工艺流程;最后,对阵列式MEMS矢量水听器进行水声校准测试。测试结果表明:阵列式水听器可靠性明显提高,灵敏度达到-179 d B(0 d B=1V/μPa),具有良好的"8"字指向性。
文摘针对传统波达方向(Direction of arrival,DOA)估计算法在小快拍数、低信噪比以及信源信号相干等条件下估计精度低等问题,提出一种基于迂回式匹配追踪算法的DOA估计方法.通过对空间按照潜在的入射角等角度进行划分,构造超完备冗余字典,采用迂回式匹配追踪算法对稀疏信号进行重构,得到信号中的非零元素按位置编号转化成对应的方向角度,即正确的DOA估计值.仿真结果表明:基于迂回式匹配追踪算法的DOA估计算法在单快拍情况下仍能得到有效估计值,在强噪声环境中也具有较好的稳健性.
基金supported by the National Natural Science Foundation of China(Grant No.11204049)the National Defence Research Funds (Grant No.7131107 and 51310040202)the Fundamental Research Funds For the Central Universities(Grant No.HEUCFR1013 and HEUCF120504)
文摘One-step patch near-field acoustical holography(PNAH) is a powerful tool for identifying noise sources from the partially known sound pressure field.The acoustical property to be reconstructed on the surface of interest is related to the partially measured pressure on the hologram surface in terms of sampling and bandlimiting matrices,which cost more in computation.A one-step procedure based on measuring of the normal component of the particle velocity is described,including the mathematical formulation.The numerical simulation shows that one-step PNAH based on particle velocity can obtain more accurately reconstructed results and it is also less sensitive to noise than the method based on pressure.These findings are confirmed by an underwater near-field acoustical holography experiment conducted with a vector hydrophone array.The experimental results have illustrated the high performance of one-step PNAH based on particle velocity in the reconstruction of sound field and the advantages of a vector hydrophone array in an underwater near-field measurement.
