机构地区: 西北工业大学航海学院
出 处: 《声学技术》 2007年第5期910-914,共5页
摘 要: 研究了一种新的非相干分布源模型。采用Jacobi-Anger级数展开,使得模型误差仅仅和级数展开的阶数有关,而和分布源空间扩展角度无关。当JA级数的阶数足够高时,分布源模型误差将会被控制在一个足够小的范围内,避免了以往利用Taylor级数展开的分布源模型中,当空间扩展角度增大时模型误差急剧增大的缺陷;利用多个对称分布能够合成非对称分布的原理,采用两个高斯分布来构造非对称分布,当控制这两个高斯分布之间的比例,非对称分布的形状也随之发生改变。新模型突破了以往分布源模型中对空间扩展角度以及分布形式的限制,具有广义性。将新模型与最速下降法进行结合,可以得到新的方位估计(DOA)。计算机仿真验证了理论的正确。 A new independently distributed source model is studied. The Jacobi-Anger (JA) series expansion technique is used in its establishment. Since the model error is only correlated with series order, it can be limited to a very small range with high order of JA series. The new model also takes the principle that a non-symmetric distribution can be composed of several symmetric distributions. Here the non-symmetric distribution is composed of two Gaussian distributions. The shape of non-symmetric distribution would change with the variation of the ratio between the two Gaussian distributions. The new model breaks the lintitation of the small spatial angular spread and symmetric distribution. Computer simulation shows that the proposed method is effective.