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用指向性函数研究了医用超声阵列换能器在具有幅度误差、相位误差及阵元失效情况下的波束特性，提出并应用幅度加权变迹处理、相位变迹处理和孔径变迹处理方法来改善阵列换能器的波束指向性．计算结果表明：相位误差和高斯分布幅度误差使旁瓣增大、栅瓣增多、波束特性变差，它们对声场特性的影响由误差的大小及分布情况共同决定．幅度加权变迹处理和孔径变迹处理都可以有效地抑制旁瓣，改变指向性；一个恒定孔径发射，可变孔径接收超声阵列系统存在一个最佳接收孔径，此时旁瓣最小．这一结论对医学超声和工业超声等领域都具有重要应用价值．
Using the directivity function to study the beam characteristics of the medical ultrasonic array transducer with amplitude error, phase error, and failure of the array element, the proposed method is applied to improve the amplitude-weighted apodization, phase apodization, and aperture apodization methods. Beam directionality of the array transducer. The calculation results show that the phase error and the Gaussian distribution amplitude error increase the sidelobe, increase the grating lobes, and degrade the beam characteristics. Their influence on the sound field characteristics is determined by the size and distribution of the error. Both amplitude-weighted apodization and aperture apodization can effectively suppress the sidelobe and change the directivity. For a constant-aperture transmission, there is an optimal receive aperture in the variable-aperture receive ultrasonic array system. This conclusion has important application value in medical ultrasound and industrial ultrasound.