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用双线列阵区分左右舷目标的延时估计方法及其实现 总被引:7,自引:4,他引:3
双线列阵声呐可以利用自身的指向特性区分左右舷目标,但是其性能受线阵间距的约束,且存在分辨盲区。本文提出利用两个单线阵接收信号的时延差区分左右舷目标的方法。该方法对线阵间距具有宽容性,并且盲区明显减小。给出了理论分析结果和实施技术方法,提出了基于内插法的延时精确估计方法,从而可以解决左右舷目标的分辨问题。 相似文献
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双线列阵左右舷目标分辨性能的初步分析 总被引:16,自引:7,他引:9
以单水听器阵列构成的单线阵声呐无法区分目标来自左舷或右舷。多线阵为解决左右舷目标的模糊问题提供了一种途径,本文讨论双线列阵左右舷目标分辨的性能,提出把波束指向方向的响应对对称方向的响应的抑制比作为评估左右舷分辨能力的一个参数,并对抑制比的性能作了初步分析,给出了理论表达及实际计算结果。理论分析结果对实际双线列阵设计中的参数选择具有重要意义。 相似文献
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针对双线列阵克服左右舷模糊问题,将双线列阵认为是由两两阵元为一组的偶极子构成的单线列阵,利用几何相移模型对目标进行左右舷分辨,经过理论分析、仿真实验和湖试实验,指出丁几何相移模型不仅能解决单频情况下的左右舷模糊问题,而且还能解决信号带宽不太宽情况下究竟能到多大相对带宽,取决于所设定的左右舷分辨增益门限)的左右舷模糊问题。该方法经湖试实验得到了很好的验证:在信噪比为5dB时,采用该方法处理时,左右舷分辨差超过7dB。在本文设定的高信噪比条件下,证明了几何相移模型的双线列阵左右舷分辨技术是有效的、可行的。 相似文献
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研究了双线阵在两种阵形畸变(轴向滑移和航向偏差)条件下的左右舷分辨性能,根据双线阵指向性函数的背瓣特性分析了阵形畸变对左右舷分辨性能的影响。理论分析表明,在无阵形畸变的理想阵形情况下,窄带信号的左右舷分辨能力取决于阵间距和信噪比,而对宽带信号,左右舷分辨能力不仅与阵间距和信噪比有关,而且还与接收信号的功率谱密度、处理频段有关。在阵形发生轴向滑移和航向不一致的情况下,在正横方向附近,左右舷分辨性能主要受双线阵的航向差影响,偏离正横方向,较大的轴向滑移会导致左右舷误判。 相似文献
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References: 《声学学报:英文版》2007,26(4):337-344
A passive synthetic aperture based on phase correction algorithm for solving the port-starboard discrimination problem in the non-aligned towed twin-line array sonar,is de- scribed.This method creates a virtual array through applying the estimated phase correction into one array of twin-line arrays.Because the synthetic virtual array is aligned with the other array in twin-line arrays,the right port-starboard discriminated results can be obtained by array processing based on the new synthetic twin-line array.The effect of proposed method has been shown by simulated and sea-trials results in towed twin-line array sonar.With low extra computational loads,the proposed method is easy to apply to the practice. 相似文献
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LIQihu 《声学学报:英文版》2007,26(1):1-6
It is well known that the single line array sonar can't identify whether the target comes from left or right. Multi-line array provides the possibility to solve the left-right ambiguity problem. The performance of left-right resolution for twin-line array is described in this paper. It is shown that the suppression ratio, which is defined as the ratio of the response in the steering direction to opposite symmetrical direction, can be considered as an index for evaluating the ability of solving left-right ambiguity. The characteristics of suppression ratio is discussed. The theoretical expression for suppression ratio and some numerical results are illustrated. The result of theoretical analysis can be used in design of twin-line array sonar. 相似文献
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LI Qihu 《声学学报:英文版》2007,26(2):97-101
The directivity function of twin-line array sonar can be used to identify left/right target. But the performance is limited by the distance between two lines and also exists the blind area for target identification. A method, which is based on the time-delay estimation between two line arrays, is proposed to identify left/right target. The method is robust with the variation of distance between two line array, the blind area is considerable decreased. The theoretical analysis results and realization method is described. An algorithm base on interpolation method for precisely estimating tune-delay of two line array are derived, therefore the left-right ambiguity problem is solved. 相似文献
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基于二元假设检验理论,研究了双线列阵对目标方位左右舷分辨的正确和错误概率。根据阵列接收窄带信号的概率密度函数,定义了左右舷判决统计量,当信号快拍数足够大时,左右舷判决统计量接近正态分布,从而可得到窄带信号的左右舷分辨概率。利用子带信号左右舷分辨概率的频率加权或波束加权,得到频率或波束加权的宽带信号左右舷分辨概率。理论和数值分析表明,窄带信号的左右舷分辨概率取决于双阵间距,而宽带信号的左右舷分辨概率对阵间距的宽容性较大。 相似文献
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A method is presented to calculate the driving-voltage weighting vector of a conformal array of underwater acoustic transmitting transducers to obtain a low-sidelobe beam pattern based on the measured receiving array manifold. The relationship among three quantities is given, which are, respectively, the radiated acoustic field, the measured receiving array manifold matrix and the driving-voltage weighting vector of the transducer array. Then, the driving-voltage weighting vector of the array is calculated using the optimization method to obtain a low-sidelobe transmitting beam pattern. At the frequency of 12.5 kHz, the receiving array manifold matrix of a 27-element conformal array is measured in an anechoic water tank. The driving-voltage weighting vector of the array is calculated using the proposed method. In addition, the computer simulation and experiments are carried out. The results agree well and show that the proposed method can obtain a low-sidelobe transmitting beam pattern and at the same time provide the largest amplitude of pressure in the axial direction when the maximum amplitude of the driving voltages of the array elements keeps unchanged. 相似文献