Power-Efficient and Low Latency Implementation of Programmable FIR filters Using Carry-Save Arithmetic

This paper presents a new Programmable Finite-Impulse Resonse (FIR) digital filter scheme based on a low latency, power efficient architecture with reduced hardware complexity. In the proposed scheme, the input data is kept in bit-parallel form, while the coefficients enter the circuit in digit-serial form. The coefficient digits are encoded using the Modified Booth algorithm to reduce the partial products required for each multiplication. The structure of the filter is based on the technique of merging adjacent multiply-add units. The computation of the intermediate results is implemented using the carry-save arithmetic. Also, the coefficient digits of adjacent multiply-add units enter the filter in digit-skew form, while the input data sample remains stable until the relative output sample is produced. Thus, the proposed architecture results in a circuit with reduced hardware cost and lower power consumption, compared to other schemes presented in the bibliography.