摘要
设计了一款基于国产芯片的便携式电离层测高仪。系统使用软件无线电的设计思想,尽可能减少了外部电路的使用。发射部分采用FPGA+高速DAC+功放天线的结构,使用DDS的方式可以产生2~30 MHz的任意波形调制信号。接收机模拟部分摒弃了传统的超外差结构,信号经天线+滤波放大后,直接经高速ADC进入FPGA处理,减少了模拟电路可能带来的噪声、温漂和非线性失真等问题,同时由于绝大部分信号处理都在数字域进行,极大地提高了系统的抗干扰能力。数字部分采用了数字混频+数字下变频的设计,可对输入的高速采样信号进行解调滤波与下变频操作,最后得到低速的基带信息经USB传输控制模块传输至上位机进行进一步处理。仿真测试与实测结果表明本设计的各项性能指标均满足要求。
A portable ionospheric altimeter based on a domestic chip is designed. The design idea of software radio is used, which reduces the use of external circuits as much as possible. For the transmitting part, the structure of FPGA+high-speed DAC+power amplifier antenna is adopted, and 2 MHz-30 MHz arbitrary waveform modulation signal can be generated by DDS. For the analog part of the receiver, the traditional superheterodyne structure is abandoned. After the signal is amplified by the antenna+filter, it is direct processed by the high-speed ADC and transmitted to the FPGA,which reduces the noise, temperature drift and nonlinear distortion that may be caused by the analog circuit. Most of the signal processing is carried out in the digital domain, which greatly improves the anti-interference ability of the system. For the digital part, the design of digital mixing and digital down-conversion is adopted, which can demodulate, filter and down-convert the input high-speed sampling signal, and finally obtain the low-speed baseband information through the USB transmission control module and transmit it to the host computer for further processing. Results of the simulation test and actual measurement demonstrate that the performance indicators of this design meet the requirements.
作者
黄鹏
杨国斌
黄春雷
李浩
HUANG Peng;YANG Guobin;HUANG Chunlei;LI Hao(School of Electronic Information,Wuhan University,Wuhan Hubei 430072,China)
出处
《电子器件》
CAS
北大核心
2023年第3期636-640,共5页
Chinese Journal of Electron Devices
