直接结构 meaning in English

direct construction

Many kinds of filters are presented in this paper , e . g . adaptive transversal filter ， direct two - order iir filter , lattice iir filter , high - order iir filter and adaptive sampling filter . because these filters have some limitations and defects , the adaptive filter of other structure is discussed in the paper
论文研究了窄带干扰抑制的几种滤波技术，主要有自适应横向滤波器、直接结构的二阶iir型滤波器、格型结构的iir型滤波器、高阶iir滤波器以及自适应采样滤波器。