An intelligent algorithm for coherent sound source localization based on a strong tracking filter

Background noise is inevitable when sensor arrays are used for aeroacoustic measurements in wind tunnels. The direct removal of background noise, however, would affect the measurement accuracy. In particular, the existing array signal processing algorithms are either invalid or inefficient for removing the noise that is coherent with the signal of interest. In this paper, an intelligent algorithm is developed to localize the coherent sound sources and background noise in real time by iteratively checking the collected data from the array. The proposed method can automatically adjust the suboptimal fading factor to extract useful information as much as possible in residual sequence. This algorithm is tested in simulations and then demonstrated in an experiment.Compared to the two existing methods, the results indicate that the new method has a good phase-shift tracking ability and rapid estimation-error convergence speed, and can achieve an acceptable performance even for low-cost acoustic sensors. Overall, the proposed method should assist array beamforming and hence benefit aeroacoustic measurement.     

X波段宽带单通道单脉冲双圆极化自跟踪天馈系统的研究

在国内首次成功研制7~12GHz宽频带单通道单脉冲自跟踪天线的基础上,对X波段宽带单通道单脉冲双圆极化自跟踪天馈系统进行研究。研究内容包括宽频带六单元照射器的设计、波束形成网络及跟踪原理的设计分析和单通道变换网络的调制与解调原理。同时,对宽频带照射器的测试、馈源和差网络的调试和天馈系统外场联调进行详细说明,并给出仿真和实验结果。测试结果非常理想,达到了设计要求。     

GPS天线阵列盲信号波束形成研究

针对GPS的抗干扰应用,给出一种不需要先验信息的GPS阵列天线盲信号波束形成新方法,用来提高GPS接收机的性能。首先建立线阵和平面阵列天线的信号模型,然后采用子空间技术剔除干扰信号,并设计多波束形成器来增强整个角空间的GPS信号。在波束形成设计中,应用Dolph-Chebyshev加权法来得到最优的主瓣波束宽度和旁瓣水平。仿真实验表明,采用盲信号波束形成方法,无论是线阵还是平面阵天线,均可以在干扰方向形成有效的零陷,在其余的角空间内增强GPS信号,从而验证了新方法的有效性和正确性。     

一种基于移相插值方法的相控阵列天线波束形成网络

文章提出了一种移相插值网络方法,可以有效降低大型相控阵列天线馈电网络的复杂性;然后基于该方法设计了一种相控阵列天线的波束形成网络;最后对13单元的一维线性阵列和19单元的面阵进行了仿真,仿真结果验证了该方法的有效性。