格型结构具有良好的抗有限字长效应能力而被应用于很多实时性较高的场合.归一化格型结构具备正交的特性,然而,对于一个Ⅳ阶数字滤波器,它需要5N+1个乘法器.为了降低其实现复杂度,并保留正交的特性,本文基于单,双,三乘法器格型单元导出了其对应的新型格型单元和格型结构.仿真结果表明,当采用单乘法器新型格型单元时,新结构抵抗有限字长误差的能力与归一化格型结构非常接近,但由于其只需2N+1个乘法器,新结构在实时信号处理中具有更大的实用价值.
Lattice structure is applied in a wide range of areas due to its excellent finite word length (FWL) properties. The normalized lattice structttre is orthogonal,but for an Nth-order digital filter,it needs 5N + 1 multipliers. To decrease the computing complexity while keeping the orthogonality unchanged, the scaled elementary lattice and the corresponding lattice structure were de- rived based on the one-, two-, and three-multiplier lattice, respectively. The simulation result indicates when the scaled one-multiplier lattice is applied,the proposed structure has close performance compared with the normalized lattice stmcture,but it is more efficient for the real-time signal processing, for it needs only 2N + 1 multipliers, much less than that in the normlized lattice structure.