基于FPGA+ARM的电离层斜向探测系统设计

Design of ionospheric oblique detection system based on FPGA+ARM

摘要:

针对传统电离层斜向探测仪结构复杂、探测信道固定、多站同步探测中相干干扰严重问题，提出一种基于现场可编程门阵列(FPGA)和先进精简指令集处理器(ARM)结构的嵌入式电离层斜向探测系统的探测方法，并给出系统结构设计。采用完全互补码解决多站同步探测的相干干扰问题，丰富了探测码制；利用数字中频接收结构在数字域中进行二次混频，避免了寄生信号和交调失真，具有标准化、模块化、扩展性强的特点；使用灵活的静态存储控制(FSMC)协议解决了控制模块之间高速并行数据传输问题，实现了数据的自动判读和频率优选。实验结果验证了系统设计的正确性及可靠性，该系统在空间物理学研究、天波超视距雷达探测、应急抢险救灾等领域有重要应用前景。

Abstract:

In view of the disadvantages of the traditional ionospheric oblique sounder like complex structure, the fixed sounding path, and the serious coherent interference among multiple stations, a detection method for the embedded ionospheric oblique sounding system based on the Field Programmable Gate Array(FPGA) and Advanced Reduced Instruction Set Computing Machines(ARM) is proposed, and the design of system structure is put forward. Firstly, the complete complementary code is adopted to solve the problem of coherent interference in simultaneous detection of multiple stations. Secondly, the digital intermediate frequency receiving structure is used for secondary mixing in the digital domain, avoiding spurious signals and intermodulation distortion, bearing the characteristics of standardization, modularization and good expansibility. The Flexible Static Memory Controller(FSMC) protocol provides a high-speed parallel data transmission method between control modules. Finally, the data automatic judgment and optimal frequency selection are realized. The experimental results verify the correctness and reliability of the design. It has important application prospects in space physics, sky-wave over-the-horizon radar detection, emergency rescue and disaster relief and other fields.