基于基阵特性提高声发射频次的方法研究

Study of Improving the Transmitting Frequency Method Based on the Array Characteristics

针对传统的多波束探测效率低等问题,提出了一种利用栅瓣来提高声发射频次的方法.在设计发射波束形成的基阵时,为了防止由于阵元间距过大产生栅瓣,通常采用密排阵的方式来规避栅瓣现象,但这样又会增加发射机的复杂程度.然而,栅瓣的存在也有其本身可以利用的价值.本文利用MATLAB对发射波束形成的方向图进行了仿真分析,总结了在不同基阵条件下主瓣和栅瓣的变化规律.介绍了利用线列阵同时向两个不同方向发射波束的方法,并利用加权法对阵列特性进行了优化.

A new method is proposed to improve the transmitting frequency by using grating lobes, which could solve the problem of low detection efficiency. When the array element spacing is large, it is easy to produce grating lobes. When designing the array of transmit beam-forming, the close--packed array can avoid generating grating lobes, the complexity of the transmitter will increase. However, the existence of the grating lobe has its value. In this paper, MATLAB was used to simulate the pattern of the transmit beam forming. Summed up the change of the grating lobe and the main lobe. This paper in- troduced a method of transmitting beams in two different directions using a line array. Finally, weigh- ting method was used to optimize the array characteristics.