Design of Linear-Phase Filter Banks with Multiplier-Less Lattice Structures

In this paper, a new multiplier-less algorithm is proposed for the design of perfectreconstruction linear-phase (PR LP) filter banks by using multiplier-less lattice structures. The coefficients in the multiplication operations have been replaced with limited number of additions and the computational complexity is reduced significantly. The property of perfection reconstruction, however, is preserved regardless the multiplier-less approximation of lattice structures in the factorization of polyphase matrix. The coefficients in the 2x2 rotation matrices of the lattice structures are expressed as sum-of-powers-of-two (SOPOT) coefficients in the parameterization processes. By using the multiplier-less rotation matrices, the unitary matrices are constructed for the lattice factorization of perfect-reconstruction linear-phase filter banks. Design examples of 5-channel and 8-channel multiplier-less linear-phase filter banks are included to validate the algorithm and implementation.