基于DFT插值的宽带波束形成器设计

Design of broadband array with frequency inyariant beam pattern by using DFT interpolation method

本文提出一种基于DFT插值的宽带波束形成器设计方法。首先推导了具有频率不变波束图的连续线阵的灵敏度函数与离散线列阵加权系数之间的关系;接着给出了基于DFT插值的宽带波束形成器设计的两个步骤:（1）使用窄带波束形成器的设计方法计算在参考频率下基阵的加权系数;（2）根据参考频率下基阵的权系数与其它子带权系数之间的关系,利用DFT插值的方法求出其它子带的加权系数。最后,给出了一个设计实例说明本文方法的有效性。

Design of broadband array with frequency invariant beam pattern by using DFT interpolation method is presented in this paper. Firstly, relationships between weights of a discrete sensor array and sensitivity distribution of a continuous linear array, which has a property of frequency invariant beam pattern, are derived. Then, two steps to design a broadband sensor array are given: 1. The weights of discrete sensor array are got at reference frequency by using traditional narrowband design method. 2. By employing the relationship between weights at reference frequency and weights at other frequency, weights at other frequency can be obtained by using DFT interpolation method. Finally, a design example shows that the proposed method is validity.