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任何相控阵系统的一个根本问题是有关旁瓣的问题。旁瓣的存在是阵列换能器固有的属性。对于声成象来说,由于旁瓣的存在将使增益与信噪比下降,从而使图象模糊或出现假目标。我们从三方面进行了旁瓣压缩实验。其一是确定换能器的结构和尺寸,以d/λ为参量给出了方向锐角、波束角、主瓣旁瓣幅值的变化规律。其二是采用幅度束控及相位束控后,使第一旁瓣由原来的56～63%下降到12～13%。其三是改变基阵孔径,使第一旁瓣降到5%左右。
A fundamental problem with any phased array system is the issue of side lobes. The presence of sidelobes is an inherent property of array transducers. For acoustic imaging, the gain and signal-to-noise ratio decrease due to the presence of side lobes, blurring the image or causing false targets. We carried out the sidelobe compression experiment from three aspects. One is to determine the structure and size of the transducer, with the d / λ as the parameter, the directions of the acute angle, the beam angle and the amplitude of the lobe of the main lobe are given. The second is the use of amplitude beam control and phase beam control, the first sidelobe from the original 56 ~ 63% down to 12 ~ 13%. The third is to change the aperture of the array so that the first sidelobe drops to about 5%.