球谐域二次Dolph-Chebyshev波束形成的设计

摘要

提出了一种球谐域二次Dolph-Chebyshev波束形成方法,该方法在常规波束形成方法和Dolph-Chebyshev波束形成方法的基础上通过平方Chebyshev多项式来计算波束形成的权值.在保持主瓣最大增益不变的情况下,通过平方Chebyshev多项式可以降低旁瓣的最大增益.因此,这种改进的波束形成在保证与前两者具有相同主瓣宽度的同时,能有效地限制旁瓣,提高声场分辨率.且在低频时具有更高的白噪声增益,从而提高球阵处理噪声的能力.仿真实验通过将这三种波束形成方法进行比较,验证了球谐域二次Dolph-Chebyshev波束形成方法的有效性.%A method for quadratic Dolph-Chebyshev beamforming in spherical harmonic domain is proposed in this paper.Based on the regular beamforming and the Dolph-Chebyshev beamforming,this method uses the quadratic DolphChebyshev polynomial to calculate the weights of the beamformer.The quadratic Dolph-Chebyshev polynomial can decrease the largest gain of the sidelobe under the condition of the constant largest gain of the mainlobe.Therefore,it can restrict the sidelobe effectively and improve the spatial resolution of the sound field with the same mainlobe width.Moreover,the higher white noise gain can be obtained at low frequencies,so spherical arrays can resist noise effectively.The simulation results demonstrated the advantages of the proposed method by comparing the three beamforming methods.