Design of Multi-Mode Digital Frequency Source Based on Embedded System

This paper proposes a multi-mode digital frequency source design based on an embedded system, constructing a hardware platform with Xilinx Zynq SoC and ADI AD9914 chip, and achieving high-precision signal generation through Direct Digital Synthesis (DDS) technology. By porting a customized Linux operating system and optimizing the software-hardware codesign architecture, the system's flexibility and scalability are significantly enhanced. The frequency source demonstrates stable performance with a frequency range of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.4-1.4 \text{GHz}$</tex> and frequency switching speed below <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$1 \mu ~\mathrm{s}$</tex>. In single-frequency continuous wave mode, it achieves spurious suppression ratios better than -70 dBc within <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$400-800 \text{MHz}$</tex> and better than -50 dBc at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{8 0 0 ~ M H z - 1. 4 ~ G H z}$</tex>.