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以环绕在刚性圆柱体上的均匀圆阵为阵列模型,分析了刚性圆柱体对圆阵响应的影响,在声场分解所得到的相位模式空间,推导了相位模式波束形成阵列和延迟求和波束形成阵列的白噪声增益和指向性指数的定量表达式,分析了它们在不同频率段的变化规律。在存在和不存在刚性圆柱体两种情况下,对两种阵列性能进行了对比分析。研究了圆阵与圆柱体之间存在间隙时对阵列接收信号及阵列性能的影响。仿真结果表明,在两种情况下相位模式波束形成处理都具有频率不变的指向性,但在低频段牺牲了阵列的鲁棒性;延迟求和波束形成处理在整个频率段具有较好的鲁棒性,但随频率的降低其波束指向性下降,直至变成各向同性阵列。存在刚性圆柱体时,两种阵列鲁棒性均有了一定的提高,前者的指向性不变,而后者的指向性得到了提高。圆阵与圆柱体之间的间隙会降低阵列在高频段的鲁棒性。
The effect of the rigid cylinder on the circular array response is analyzed with the uniform circular array around the rigid cylinder as an array model. The phase pattern beamforming array and the delayed summation beamforming The quantitative expressions of the white noise gain and the directivity index of the array are analyzed and their variations in different frequency bands are analyzed. In both the presence and absence of rigid cylinders, the performance of the two arrays was compared. The effect of the gap between the circular array and the cylinder on the array receive signal and array performance was investigated. The simulation results show that the phase-mode beamforming processing has the frequency-invariant directivity in both cases, but sacrifices the robustness of the array at low frequencies. The delay-sum beamforming process has better robustness over the entire frequency band However, as the frequency decreases, the beam directivity decreases until it becomes an isotropic array. In the presence of a rigid cylinder, the robustness of both arrays is improved to a certain extent, the former’s directivity is unchanged and the latter’s directivity is improved. The gap between the circular array and the cylinder reduces the robustness of the array at high frequencies.