A novel FPGA-based approach for digital waveform generation using orthogonal functions

This paper presents a novel approach for the generation of periodic waveforms in digital form using Field Programmable Gate Array ( FPGA) and orthogonal functions. The orthogonal function consists of a set of Rademacher-Walsh Functions, and utilizing these functions, virtually any periodic waveform can be synthesized. Recent technological advancements in FPGA and availability of sophisticated digital design tools have made it possible to realize high-speed waveform generator in a cost-effective way. We demonstrate the proposed technique for the successful generation of Trapezoidal, Sinusoidal, Triangular waveforms, and a complex version of these waveforms. Simulation results for the various waveforms implemented in Xilinx Spartan-3 (XC3S200-4FT256) FPGA are presented both in analog and digital forms, and validated in MATLAB. The designed circuit can be easily integrated as a module for System-on-Chip (SoC) for on-chip waveform generation.