共查询到18条相似文献,搜索用时 111 毫秒
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低频宽带大功率换能器是现代水声发展的一项关键技术。换能器与功放匹配是宽带大功率水声发射的关键技术之一,本文对一种宽带大功率匹配匹配网络进行了设计分析,通过该匹配网络可改善宽带匹配效果,同时拓宽工作频带。文中还给出了一台功放驱动两只宽带换能器的匹配网络。 相似文献
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圆柱阵换能器具有水平全向的优势,已广泛应用在水声探测领域。文章研究了一款宽带圆柱阵,利用匹配层技术拓宽圆柱阵阵元的带宽,通过有限元仿真优化单个换能器阵元带宽、发送电压响应和阻抗等参数。同时通过仿真以阵元错位密集方式形成圆柱阵,对阵元的个数及排列方式进行仿真优化,制作了一款宽带圆柱阵并进行了测量,圆柱阵直径为400 mm,高度为435 mm,圆柱阵的工作频段为20~30 kHz,频带内起伏3 dB,最大发送电压响应为160.5 dB,圆柱阵-3 dB水平波束宽度为360°。 相似文献
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1.引 言 宽带大功率水声换能器由于具有优良的脉冲响应特性,且能够接收和发射各种信号,它已不仅是高分辨力声纳的关键部件,而且已成为水下通信系统必不可少的关键部件。 本文所述的换能器是附加有声匹配板的Tonpilz换能器(Tonpilz换能器即串并联电路机械模拟换能器—译注),它是根据多模式滤波器合成理论设计的。我们用这种方法 相似文献
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匹配层厚度振动换能器研究 总被引:2,自引:0,他引:2
随着水声信号处理技术的发展,对宽带信号的需求日益增长。换能器的带宽是宽带信号处理的基础,而匹配层技术是拓宽厚度振动换能器频带最有效的方法。研究了多匹配层厚度振动换能器的设计方法,建立了复数形式的多匹配层厚度振动换能器等效网络模型,仿真研究了匹配层参数对换能器响应带宽的影响,指出了单、双匹配层在拓宽换能器带宽方面的限制,还指出匹配层的最佳厚度并非一定就是四分之一波长。在此基础上,制作了单、双匹配层换能器样品,对仿真结果进行了试验验证。测试结果和仿真结果符合得很好。 相似文献
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在基于多模振动的超宽带声基阵的研究中,需要了解该阵同单模振动相比的电声效率的变化。为此,必须要对宽带声阵的空间增益有一个正确的可信的估算。本文就是按实测的声阵指向性图通过拟合指向性函数,然后经数学处理得到空间增益,再经简单换算得到电声效率,以便正确评估匹配层宽带换能器基阵的性能。 相似文献
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利用角谱理论得到了圆形活塞换能器阵元组阵后作用在平面悬浮物体上的声辐射力分布公式。通过数值仿真,分析了换能器频率、阵元间距以及阵元数目对声辐射力分布的影响。计算结果表明,换能器组阵使得声辐射力分布的指向性变窄,强度增强;随着换能器频率的提高、阵元间距的增大以及阵元数目的增多,声辐射力分布的主瓣更尖锐,但阵元间距的增大会使声辐射力分布的旁瓣增高。为了改善声辐射力的空间分布,采用伪逆矩阵算法,以能量增益为目标函数,通过调节换能器阵元表面振动速度的幅值和相位来形成多焦点的声辐射力分布,为阵列换能器声辐射力分布的调控和声悬浮稳定性的研究提供帮助。 相似文献
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Ramesh R Ebenezer DD 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2008,55(9):2079-2083
A method is presented to determine the equivalent circuits of broadband transducers with 2 resonances in the frequency band of interest. The circuit parameters are refined by least-squares fitting the measured electrical conductance data with this model. The method is illustrated by computing the conductance and susceptance of the equivalent circuits of 3 types of broadband transducers and comparing them with the measured values. The equivalent circuit of a transducer is necessary for designing filters that match the impedances of the transducer and the power amplifier that drives the transducer. 相似文献
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Thiagarajan S. Martin R.W. Proctor A. Jayawadena I. Silverstein F. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1997,44(5):1172-1174
This study describes a method of applying very thin broadband matching layers to 2 mm diameter 20 MHz transducers. Dual layer acoustic matching between the ceramic and the medium at the front face of the transducer was accomplished by selecting 1/4 wavelength glass layers from a commercial source, epoxying them to the ceramic, and vapor depositing parylene to 1/4 wavelength thickness on the glass. A 8 dB fractional bandwidth of 0.75 and insertion loss of -10 dB was found on the average for these transducers. This method allowed fabricating probes that performed well, were reproducible, provided both a matching and protection coating, and could be fabricated in a practical manner 相似文献
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Qingshan Yao Bjorno L. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1997,44(5):1060-1066
Head flapping has often been considered to be deleterious for obtaining a tonpilz transducer with broadband, high power performance. In the present work, broadband, high power tonpilz transducers have been designed using the finite element (FE) method. Optimized vibrational modes including the flapping mode of the head are effectively used to achieve the broadband performance. The behavior of the transducer in its longitudinal piston mode and in its flapping mode is analysed for in-air and in-water situations. For the 37.8% bandwidth of the center frequency from 28.5 to 41.8 kHz, the amplitude variation of the transmitting voltage response (TVR) does not exceed ±2 dB and a maximum TVR of 146.8 dB (ref. 1 μPa/volt at 1 meter) is obtained. Reasonable agreement between the experimental results and the numerical results is achieved. A maximum sound pressure level of 214.8 dB can be expected. Further numerical calculation indicates that there is potential for increasing the bandwidth by varying other parameters in the design 相似文献
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为了解决E类功放工作带宽过窄的问题,对E类功放的输入、输出匹配网络提出了一种改进方案.该方案中输出匹配网络采用微带线结构与切比雪夫低通匹配网络相结合的方法,在较宽的工作带宽内有效地抑制了谐波;并采用阻抗变换方法设计了含闭式解的宽带带通输入匹配网络,明显增强了输入匹配网络设计的灵活性.利用该方案,同时采用多谐波双向牵引技术得到功率管的最佳源阻抗和负载阻抗,基于CGH40010F功率管设计了一款应用于L波段的宽带高效率E类功放.测试结果表明,在输入功率为28dBm,漏极偏置电压VDS=28V,栅极电压VGS=-3.3V时,在整个L波段频率范围内漏极工作效率大于65%,最高达到83%,输出功率为39~41.1dBm,增益为11~13.1dB,增益平坦度为±1dB.这一结果验证了该改进方案的有效性,使得E类功放具有宽带宽、高效率的性能. 相似文献