Design and Implementation of a Signal Generator Based on FPGA

Direct Digital Synthesis (DDS) technology offers advantages such as high frequency resolution, fast switching speed, and continuous phase. Consequently, it is widely applied in fields such as wireless communication, satellite navigation, and electronic reconnaissance. Using DDS technology, along with development tools ModelSim SE and Quartus Ⅱ 13.0 and the hardware description language Verilog HDL, this study completed the design, simulation, and online logic debugging and analysis of the signal generator. The system is capable of: (1) outputting sine, triangular, and square waves; (2) adjusting signal frequency, amplitude, and duty cycle via buttons; and (3) observing the output signal using an oscilloscope. Simulation and practical verification show that the output frequency ranges from 1 Hz to 1 MHz, the output peak-to-peak amplitude is continuously adjustable within 0–6.4 V, and the duty cycle is continuously adjustable from 0% to 100%. The implementation of the system provides a referable teaching case for students to learn Field Programmable Gate Array (FPGA) courses.