Design of Digital Control System for High-performance Ionosonde Based on FPGA
-
摘要: 为建立天地一体化电磁观测系统,实现电离层等的实时准确观测,为地震机理的研究与地震预报工作提供科学有效的数据,提出了一种高性能电离层测高仪数控系统设计方案将应用于电磁卫星的地面同步验证系统中,给出了数控系统的时序控制单元、发射单元和接收单元等的具体实现.在收发延迟可变的雷达时序控制下,发射单元利用直接数字合成技术产生1~30MHz的脉冲信号,40位类巴克码对脉冲信号进行二进制相位调制编码,随后交替发射正交极化波;接收单元利用高速模数转换器实现信号的数字化,采用FPGA技术进行下变频处理.本数控系统的设计可直接获取回波信号的极化信息,高度分辨率为1.5km,探测周期小于2min.实验结果表明,该数控系统方案切实可行.Abstract: This paper presents a high-performance ionosonde's digital control system design scheme, which is consisted of timing control unit, transmitting unit and receiving unit. This system is employed in electromagnetic synchronization verification system on the ground to establish integrated electromagnetic observation systems of heaven and earth with the electromagnetic satellite, to realize real-time accurate observation of the ionosphere, and to provide scientific and effective data for the study of earthquake mechanism and earthquake prediction. Under the radar timing control with variable transmission and reception delay, the transmitting unit uses Digital Frequency Synthesis (DDS) technology to generate pulse signals with the frequency range is 1MHz to 30MHz. The pulse signal is encoded by the 40-bit quasi-Barker codes in binary phase shift keying modulation, and orthogonally polarized waves are transmitted alternately by the antenna. The analog-to-digital conversion of the receiving unit is realized by a high-speed Analog-to-Digital Converter (ADC), and the Digital Down-Conversion (DDC) is carried out by the Field Programmable Gate Array (FPGA) technology. The polarization information of the echo signal can be caught by the ionosonde. The height resolution of the ionosonde is 1.5km, the detection period of the ionosonde is less than 2min. The verification results show that the digital control system scheme is feasible.
-
Key words:
- Digital ionosonde /
- Digital control system /
- FPGA /
- Quasi-Barker codes /
- DDC
-
[1] BLEIER T, FREUND F. Earthquake warning systems[J]. IEEE Spectrum., 2005, 42(12):22-27 [2] CAI Run, WU Zhen, TAN Dacheng, et al. A summary of electromagnetic anomalies before earthquakes[J]. South China J. Seismol., 2018, 38(1):1-16(蔡润, 武震, 谭大诚, 等. 地震前的电磁异常综述[J]. 华南地震, 2018, 38(1):1-16) [3] WANG Yi, CAO Qunsheng, YUAN Xiao. Electromagnetic propagation anomalies during earthquakes[J]. J. Nanjing Univ. Aeronaut. Astron., 2013, 45(4):479-484(王毅, 曹群生, 袁肖. 地震期间的超低频电磁波传播异常研究[J]. 南京航空航天大学学报, 2013, 45(4):479-484) [4] LIU J Y, CHEN Y I, PULINETS S A, et al. Seismo ionospheric signatures prior to M6.0 Taiwan earthquakes[J]. Geophys. Res. Lett., 2000, 27(19):3113-3116 [5] ZHANG Donghe, LI Qiang, QIN Jiansheng, et al. Study of the response of the ionosphere over sun-lit boundary region to solar flare[J]. Chin. J. Space Sci., 2006, 26 (5):321-325(张东和, 李强, 覃健生, 等. 日照边缘区域电离层对耀斑的响应特点研究[J]. 空间科学学报, 2006, 26(5):321-325) [6] WANG Lanwei, HU Zhe, SHEN Xuhui, et al. Data processing methods and procedures of CSES satellite[J]. J. Remote Sens., 2018, 22(S1):39-55(王兰炜, 胡哲, 申旭辉, 等. 电磁监测试验卫星(张衡一号)数据处理方法和流程[J]. 遥感学报, 2018, 22(S1):39-55) [7] ZHU Zhengping, NING Baiqi, SUN Fenglou, et al. Study of passive receiving observation mode for ionospheric digital ionosonde[J]. Chin. J. Space Sci., 2009, 29(4):389-396(朱正平, 宁百齐, 孙奉娄, 等. 电离层数字测高仪被动接收观测模式研究[J]. 空间科学学报, 2009, 29(4):389-396) [8] REINISCH B W, GALKIN I A, KHMYROV G M, et al. New Digisonde for research and monitoring applications[J]. Radio Sci., 2009, 44(1):1-15 [9] WANG Shun, CHEN Ziwei, ZHANG Feng, et al. A new design for digital ionosonde[J]. Chin. J. Space Sci., 2014, 34(6):849-857(王顺, 陈紫微, 张锋, 等. CAS_DIS数字电离层测高仪系统研制[J]. 空间科学学报, 2014, 34(6):849-857) [10] GONG W, CUI X, PAN L. Design and application of the digital multifunctional ionosonde[J]. IET Radar, Sonar Nav., 2016, 10(7):1303-1309 [11] LAN Jiaping, NING Baiqi, ZHU Zhengping, et al. Development of agile digital ionosonde and its preliminary observation[J]. Chin. J. Space Sci., 2019, 39(2):167-177(蓝加平, 宁百齐, 朱正平, 等. 敏捷数字电离层测高仪系统研制及初步观测[J]. 空间科学学报, 2019, 39(2):167-177) [12] CHEN Kun. Design of the ionosonde[D]. Wuhan:South-central University for Nationalities, 2009:6-26(陈锟. 电离层数字测高仪的研制[D]. 武汉:中南民族大学, 2009:6-26) [13] HERWADE P A, GAIKWAD S V. Design of broadband delta loop antenna and balun for ionosonde application[C]//Proceedings of the 2015 Annual IEEE India Conference (INDICON). New Delhi:IEEE, 2015:1-4 [14] QIAO L, CHEN G, CUI X, et al. Comparison of the traditional ionosonde and the digital ionosonde based on direct digitization[J]. IEEE Geosci. Remote Sens. Lett., 2017, 14(2):198-202 [15] WANG Shun, CHEN Ziwei, ZHANG Feng, et al. A method for separating O wave and X wave in digital ionosonde[J]. Chin. J. Space Sci., 2014, 34(2):186-193(王顺, 陈紫微, 张锋, 等. 一种数字电离层测高仪系统中O波与X波的分离方法[J]. 空间科学学报, 2014, 34(2):186-193) [16] SUN Zhishen, LIU Xiaojun, ZHAO Bo. Application of complementary codes in ionospheric detection[J]. Sci. Technol. Eng., 2011, 11(21):5047-5052(孙直申, 刘小军, 赵博. 互补码在电离层探测中的应用[J]. 科学技术与工程, 2011, 11(21):5047-5052) [17] ZHOU Jianyong. Development and research on data processing platform for ionosonde[D]. Wuhan:South-central University for Nationalities, 2009:50-54(周健勇. 电离层数字测高仪数据处理平台的研制[D]. 武汉:中南民族大学, 2009:50-54) [18] ZHANG Weiqin. Design and implementation of radio frequency circuit in short wave medium frequency digital platform[D]. Chengdu:University of Electronic Science and Technology of China, 2018:1-22(张伟琴. 短波中频数字化平台中射频电路的设计与实现[D]. 成都:电子科技大学, 2018:1-22) [19] LIU Wei. The technology of digital down converter base on FPGA[D]. Xi'an:Xidian University, 2017(刘伟. 数字下变频技术及其FPGA实现[D]. 西安:西安电子科技大学, 2017) [20] HE Yunliang, GENG Shuqin, WANG Jinhui. Design and simulation of FIR digital filter based on Verilog[J]. Modern Electron. Tech., 2016, 39(10):1-4(何蕴良, 耿淑琴, 汪金辉. 基于Verilog的FIR数字滤波器设计与仿真[J]. 现代电子技术, 2016, 39(10):1-4)
点击查看大图
计量
- 文章访问数: 344
- HTML全文浏览量: 69
- PDF下载量: 34
- 被引次数: 0