Efficient Mutliplierless Polyphase FIR Filter based on New Distributed Arithmetic Architecture
This paper present an efficient polyphase multiplierless finite impulse response (FIR) architecture based on new distributed arithmetic (NEDA). The polyphase structure is based on the decomposition of the transfer function in subfilters connected in parallel. The multiplications involved on each subfilter are replaced by an adder array implemented by NEDA. These subblocks presents a different distribution of Is and Os on the NEDA matrix compared with the implementation of the filter in a direct form or transposed form. NEDA presents a bottleneck that is reduced by a balance between a larger filter order and a reduced coefficient wordlength size impacting the whole structure with this tradeoff. This new architecture involves a reduced number of adders in their implementation without significant overhead. The results presented are compared with previous approaches showing superior result around of 34% average reduction on the total number of adders. Additionally, the proposed design method for FIR filter is simple.