数字化短波调制解调器设计  

Design of a Digital HF Modem

作　　者：梁津垚[1] 潘龙禹 丁良辉[1] 杨峰[1] 钱良[1] 

机构地区：[1]上海交通大学未来媒体网络协同创新中心,上海200240 [2]中国民航大学飞行技术学院,天津300300

出　　处：《电讯技术》2015年第11期1283-1289,共7页Telecommunication Engineering

基　　金：国家高技术研究发展计划(863计划)项目(2012AA011701);国家自然科学基金资助项目(61301117)~~

摘　　要：为了实现高速、可靠、易于实现的数字化短波通信,提出了一种基于通用计算机的调制解调器设计方案。为了实现高可靠性的数字短波信号传输,搭建了用户端到用户端的转换平台设计,其中,模拟短波电台提供系统收发天线,使用计算机声卡实现数字信号与音频之间的数模/模数互转,使用计算机处理器(CPU)调制解调。根据短波通信功率受限的特点,使用恒包络调制——高斯最小频移键控(GMSK)作为调制方式。为了实现快速准确的时间同步,设计了一种多训练序列分段插入的帧结构方案。计算机仿真和实测结果表明,该调制解调器在信噪比15 d B下可达到10-5的误比特率,实现可靠短波通信。In order to realize digital high frequency(HF) communication with high speed,reliability and easy operation,this paper designs an HF modem based on computer. The end-to-end platform design pro-vides reliable HF signal transmission. Analog HF radio stations provide transmitter antenna and receiver antenna. Computer soundcard is used to be the analog-to-digital/ digital-to-analog module and computer CPU is the core for signal processing. According to the power limitation character of HF communication, constant envelope modulation or Gaussian Filtered Shift Keying ( GMSK) is chosen in design. To realize fast and accurate time synchronization,a new frame structure with multiple short training sequences inserted in is proposed. Both of the simulation results and the real tests show that 10-5 bit error rate( BER) is a-chieved in 15 dB signal-to-noise ratio(SNR) with low data speed. The modem meets the need of HF communication.

关 键 词：数字化短波通信 调制解调器设计 模拟短波电台 频偏估计 

分 类 号：TN915.05[电子电信—通信与信息系统]