Single-Bit and Conventional FIR Filter Comparision in State-of-Art FPGA

The performance/area characteristics of a Sigma Delta Modulated Ternary FIR filter and a conventional FIR filter are compared. The implementation of both filters has been carried out in VHDL using a hierarchical adder tree organization in both pipelined and non-pipelined modes and synthesized on a small number of representative commercial FPGA devices. At a similar spectral performance, the ternary FIR filter achieved 40% higher performance than its conven-tional equivalent using a 12x12 bit multiplier with much lower I/O and a slightly smaller area. This performance ratio was increased to 70% in pipelined mode. Clock speeds in excess of 200MHz at 32 OSR were achieved on a low-cost FPGA and over 400MHz on a high-performance device.