Area efficient FIR filters for high speed FPGA implementation

A new algorithm that synthesises multiplier blocks with low hardware requirement suitable for implementation as part of full-parallel finite impulse response (FIR) filters is presented. Although the techniques in use are applicable to implementation on application-specific integrated circuit (ASIC) and Structured ASIC technologies, analysis is performed using field programmable gate array (FPGA) hardware. Fully pipelined, full-parallel transposed-form FIR filters with multiplier block were generated using the new and previous algorithms, implemented on an FPGA target and the results compared. Previous research in this field has concentrated on minimising multiplier block adder cost but the results presented here demonstrate that this optimisation goal does not minimise FPGA hardware. Minimising multiplier block logic depth and pipeline registers is shown to have the greatest influence in reducing FPGA area cost. In addition to providing lower area solutions than existing algorithms, comparisons with equivalent filters generated using the distributed arithmetic technique demonstrate further area advantages of the new algorithm.