针对数字信号通过基带系统远程传输问题, 分析了对信号进行编码和频谱变换的原理。在系统结构设计的基础上, 重点介绍了采用FPGA 编程实现基带信号编码、频谱变换、位定时提取的过程, 给出了关键环节的仿真波形。利用伪码对实际系统进行了测试, 证明能可靠地完成基带信号的传输。-For digital signal through the base-band system long-distance transmission problem, analysis of the signal coding and spectrum transform principle. In the system based on the structural design, focusing on the use of FPGA programming baseband signal coding, spectrum transform, bit timing extraction process, and gives a key link in the simulation waveforms. Using pseudo-code of the actual system has been tested, proven to be reliable and complete base-band signal transmission.