数字脉冲间隔调制(DPIM)对缓存性能要求较高,相对于定长型调制方式存在一定的劣势。为此,提出了一种新型定长双宽数字脉冲间隔调制(FDD-DPIM),给出其符号结构,通过仿真和实验对比分析了二进制开关键控(OOK)、DPIM、定长数字脉冲间隔调制(FDPIM)、定长数字振幅脉冲间隔调制(FDAPIM)以及双幅度定长数字脉冲间隔调制(DAFDPIM)的带宽需求、平均发射功率及差错性能。结果表明:提出的FDD-DPIM具有更高的带宽利用率和平均发射功率,同时差错性能优于DAFDPIM,在可见光通信系统中具有一定的应用前景。 Digital Pulse Interval Modulation (DPIM) has a high cache performance requirement and has some disadvantages over fixed-length modulation. For this reason, a new fixed-length double-width digital pulse spacing modulation (FDD-DPIM) is proposed and its symbolic structure is given. By comparing the simulation and experiment, the binary open-loop keying (OOK), DPIM, fixed length digital pulse spacing FDPIM, FDAPIM, and DAF DPIM, average transmit power and error performance. The results show that the proposed FDD-DPIM has higher bandwidth utilization and average transmit power, and its error performance is better than that of DAFDPIM. It has certain application prospect in visible light communication system.