高级检索

基于正交判据的圆形阵列波束形成器设计

Design of Circular Array Beamformer Based on Orthogonal Criterion

  • 摘要: 为解决圆形差分传声器阵列在波束成形过程中的高计算复杂度与低时间分辨率问题,利用圆形阵列特殊的几何特性,通过构造波束形成器和波束方向图预期零点方向之间的正交判据,提出了一种基于零点区间特征信息的宽带波束形成器设计方法。首先,根据目标信号的入射角度和波束方向图的预期零点的角度,将波束形成器的设计转化为最优化问题并设计求解;其次,通过优化零点数量与白噪声增益,设计了一系列白噪声增益与指向性因子可调节的波束形成器,并证明了其与传统方法设计的波束形成器等价;最后,结合区间内零点与噪声的特征信息,设计了信噪比增益可调的波束形成器。为验证波束成形效果,设计圆形传声器阵列与零点特征信息,进行宽带波束方向图与信噪比增益的仿真,仿真结果验证了该方法的可行性和有效性。可见,当给定波束方向图预期零点信息时,该方法设计的波束形成器能够产生频率不变的波束方向图,并实现信噪比增益的可控。

     

    Abstract: In order to solve the high computational complexity and low temporal resolution issues in the beamforming process of circular differential microphone arrays, a broadband beamformer design method based on the zero-point interval characteristic information is proposed, leveraging the unique geometrical properties of the circular array. This method establishes an orthogonal criterion between the beamformer and the anticipated zero-point direction of the beam pattern. Initially, the design of the beamformer is transformed into an optimization problem, considering the incident angle of the target signal and the angle of the anticipated zero points of the beam pattern, and a solution is designed. Subsequently, by optimizing the number of zeros and the white noise gain, a series of beamformers with adjustable white noise gain and directivity factor are designed, and their equivalence to beamformers designed by traditional methods is proven. Finally, using the characteristic information of zeros and noise within a given interval, a beamformer with adjustable signal-to-noise ratio gain was designed. To validate the beamforming effect, a circular microphone array and the zero-point characteristic information are designed, and simulations of the broadband beam pattern and signal-to-noise ratio gain are conducted. The simulation results confirm the feasibility and effectiveness of this method. It is evident that when the anticipated zero-point information of the beam pattern is given, the beamformers designed by this method can produce a frequency-invariant beam pattern and achieve controllable signal-to-noise ratio gain.

     

/

返回文章
返回