基于GPU 的PCM/FM 信号非相干鉴频解调算法

面向未来任务日益多样化，试验环境日趋复杂化，传统基于FPGA 的脉冲编码调制/调频(pulse codemodulation/frequency modulation，PCM/FM)遥测系统存在软硬件紧耦合、研发周期长、升级维护困难等缺点，无法满足未来遥测系统大规模部署对弹性、灵活和敏捷的需求。针对以上问题，设计基于GPU 的PCM/FM 信号非相干鉴频解调实现方法。根据算法原理和GPU 并行方法设计出基于GPU 的并行解调实现方法，分别从并行数字下变频、并行FIR 滤波和并行差分鉴频3 部分分析具体模块的并行化实现方法。实验结果表明：在码速率为10 Mbps、每处理1 s 数据的条件下，基于GPU 的非相干鉴频过程消耗的时间约为426.867 ms，满足解调的实时性要求；解调增益稍优于传统基于FPGA 的PCM/FM 遥测基带，有约0.1 dB 的解调增益。

Non-coherent Demodulation Algorithm for PCM/FM Signal Based on GPU

With the increasing diversification of future-oriented tasks and the increasing complexity of test environment,the traditional pulse code modulation/frequency modulation (PCM/FM) telemetry system based on FPGA has someshortcomings, such as the tight coupling of hardware and software, the long development cycle, and the difficulty ofupgrade and maintenance. It can not meet the needs of large-scale deployment of future telemetry systems for elasticity,flexibility and agility. In order to solve the above problems, a GPU-based non-coherent demodulation method for PCM/FMsignals is designed. The parallel demodulation method based on GPU is designed according to the algorithm principle andGPU parallel method and the parallel implementation method of specific modules is analyzed from the 3 parts of paralleldigital down conversion, parallel FIR filtering and parallel differential frequency discrimination. The experimental resultsshow that the non-coherent frequency discrimination process based on GPU consumes about 426. 867 ms when the coderate is 10 Mbps and the data is processed every second, which meets the real-time requirements of demodulation, thedemodulation gain is slightly better than the traditional PCM/FM telemetry baseband based on FPGA, with about 0.1 dBdemodulation gain.