说明：  宽带聚焦的目的是通过一个聚焦变换矩阵，使得对应于不同频段的数据变换成同一个中心频率的数据，从而形成相关矩阵。这里的关键就在于聚焦矩阵的选取，不同的选择对应于不同的算法。
(Focus on the purpose of broadband are focused through a transformation matrix which corresponds to a different band with the data converted into a center frequency of the data, to form the correlation matrix. The key here is to focus on the matrix selected, different options correspond to different algorithms.)