Optimized Design of Direct Digital Frequency Synthesizer Based on Hermite Interpolation
Kunpeng Zhou1, Qiaoyu Xu1, Tianle Zhang1
1College of Mechanical and Electrical Engineering, Henan University of Science and Technology, Luoyang 471000, China.
Sensors (Basel, Switzerland)
|October 16, 2024
Summary
This study introduces an optimized Direct Digital Frequency Synthesis (DDFS) method using cubic Hermite interpolation to improve spectral purity and reduce resource usage in embedded systems.
Area of Science:
- Digital Signal Processing
- Embedded Systems Engineering
Background:
- Direct Digital Frequency Synthesis (DDFS) often suffers from suboptimal spectral purity in resource-constrained environments.
- Amplitude quantization during DDFS digitalization introduces spurious issues and requires significant data storage.
Purpose of the Study:
- To propose an optimized DDFS technique using cubic Hermite interpolation.
- To enhance spectral purity and reduce resource utilization in DDFS for embedded systems.
Main Methods:
- Implemented DDFS hardware architecture on a Field-Programmable Gate Array (FPGA).
- Extracted interpolation parameters using cubic Hermite interpolation, combining derivative relations of sine/cosine functions with dual-port ROM.
- Employed single-quadrant ROM compression technology to minimize storage space.
Main Results:
- Achieved a ROM resource compression ratio of 1792:1.
- Obtained a 14-bit output Spurious-Free Dynamic Range (SFDR) of -88.134 dBc.
- Significantly improved amplitude quantization precision and reduced spurious levels.
Conclusions:
- The proposed optimized DDFS scheme enhances spectral performance and resource efficiency.
- This technique is highly suitable for resource-constrained embedded systems, radar, and communication systems.
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