基于FPGA的Multi-h CPM高速解调系统设计与实现  

Design and Implementation of High-speed Demodulation System for Multi-h CPM Signal Based on FPGA

作　　者：刘誉楷 刘荣科[1,2] 陈祺治 LIU Yukai;LIU Rongke;CHEN Qizhi(School of Electronic and Information Engineering,Beihang University,Beijing 100191,China;Shenzhen Institution of Beihang University,Shenzhen 518063,China)

机构地区：[1]北京航空航天大学电子信息工程学院,北京100191 [2]深圳北航新兴产业技术研究院,广东深圳518063

出　　处：《无线电通信技术》2023年第5期912-923,共12页Radio Communications Technology

基　　金：北京市自然科学基金(L202003)。

摘　　要：多指数连续相位调制(Multi-h Continuous Phase Modulation,Multi-h CPM)作为一种高效的调制方式,具有良好的频谱效率和抗干扰能力,在卫星通信领域有着广泛的应用价值。但是Multi-h CPM的解调算法计算复杂度较高,为了实现高速数据传输能力,需要较高的硬件资源开销。因此基于现场可编程门阵列(Field Programmable Gate Array,FPGA)平台的高并行度数据处理能力,设计了一种Multi-h CPM高速解调系统,采用了软输出维特比算法(Soft Output Viterbi Algorithm,SOVA)实现了Multi-h CPM信号解调,并通过早迟门和升降频门实现了时频同步功能。为了降低算法的计算复杂度,本系统引入了倾斜相位(Tilted Phase,TP)算法和频率脉冲响应截断(Frequency Pulse Truncation,FPT)算法减少了Viterbi过程的网格状态数,降低了系统的资源开销。通过仿真和实际测试,验证了所提出的解调系统的有效性,并表明该系统具有良好的解调性能和系统稳定性。Multi-h Continuous Phase Modulation(Multi-h CPM) is an efficient modulation technique with high spectrum efficiency and anti-jamming ability,and has extensive applications in of satellite communications.However,the high computational complexity of the demodulation algorithm requires high resource consumption to ensure fluent data transmission with high speed.Therefore,a high-throughput Multi-h CPM demodulation system based on the Field Programmable Gate Array(FPGA) platform is designed,which uses a Soft Output Viterbi Algorithm(SOVA) to demodulate the Multi-h CPM signal,and early-late gates and up-down frequency gates are applied to achieve time and frequency synchronization.To reduce the computational complexity of the algorithm,Tilted Phase(TP) and Frequency Pulse Truncation(FPT) technologies are introduced to reduce the number of Viterbi states and lower the computational cost of the system.Through simulations and experiments,the effectiveness of the proposed demodulation system is verified,and it is shown that the system has good demodulation performance and stability.

关 键 词：多指数连续相位调制 软输出维特比算法 高速解调系统 现场可编程门阵列 

分 类 号：TN919.6[电子电信—通信与信息系统]