无线光通信中的定长双幅度脉冲间隔调制  

Fixed Length Dual-Amplitude Pulse Interval Modulation for Optical Wireless Communications

作　　者：黄爱萍[1] 樊养余[1] 李伟[1] 白勃[1] 

机构地区：[1]西北工业大学电子信息学院,陕西西安710072

出　　处：《中国激光》2009年第3期602-606,共5页Chinese Journal of Lasers

基　　金：重点实验室基金(9140C5301010701);陕西省自然科学基金(2007F10)资助课题

摘　　要：在无线光通信中,为解决脉冲位置调制(PPM)需要符号同步和数字脉冲间隔调制(DPIM)符号长度不固定造成调制器等待或缓冲器溢出的问题,提出了一种新的调制方式一定长双幅度脉冲间隔调制(FDAPIM),分析了它的符号结构、发射功率、带宽需求以及在高斯白噪声下的差错性能,并和开关键控(OOK)、脉冲位置调制(PPM)、数字脉冲间隔调制(DPIM)、定长数字脉冲间隔调制(FDPIM)等调制方式进行了比较。理论分析与仿真结果表明,FDAPIM的误包率劣于PPM和DPIM,接近于FDPIM,但明显优于OOK。虽然FDAPIM的带宽要求较高,但其带宽效率和功率效率都优于FDPIM,且不需要符号同步,相对于PPM系统,实现的复杂性大大简化;相对于DPIM,其符号长度固定,不会引起调制器等待或缓冲器溢出。因此FDAPIM应用于无线光通信系统具有一定优势。In order to solve the problem of symbol synchronization in pulse position modulation (PPM) and modulator waiting or bugger overflow resulting from the unfixed length in pulse interval modulation (DPIM) in optical wireless communications, a novel fixed length dual-amplitude pulse interval modulation(FDAPIM) is discussed. The symbol structure, transmission power, bandwidth requirement and error performance of FDAPIM in a non-dispersive channel are presented and compared with OOK, PPM, DPIM and FDPIM. Simulations show that the packet error rate of FDAPIM is higher than that of PPM and DPIM, which is similar to FDPIM and less than OOK obviously. Moreover, FDAPIM, which does not need symbol synchronization and has fixed symbol length, helps to simplify the receiver and solve the problem of modulator waiting and bugger overflow. It is superior in wireless optical communications system.

关 键 词：无线光通信 双幅度脉冲间隔调制 发射功率 带宽需求 误包率 调制方式 

分 类 号：TN929.1[电子电信—通信与信息系统]