光通信中一种有效的差分脉冲位置宽度调制

考虑脉冲位置调制(PPM)在解调时需要严格的时钟同步和符号同步,而且功率越高,时隙越窄的问题,结合差分脉冲位置调制(DPPM)和脉冲宽度调制(PWM)提出了一种有效的调制方式--差分脉冲位置宽度调制(DPPM+PWM).研究了采用DPPM+PWM的红外通信系统在加性高斯白噪声干扰下的性能,对DPPM+PWM的符号结构、发射功率、带宽需求、传输容量以及误包率等特性进行了分析,并通过仿真与开关键控(OOK),PPM,PPM等调制方式进行了比较.结果表明DP-PM+PWM频带利用率高,传输容量大,不需要符号同步,且增加了脉冲信号的长度,大大简化系统实现,是一种很有实际应用价值的调制方式.

Differential-Pulse-Position-Width Modulation for Optical Communication

In order to solve the problems of symbol synchronization and narrow pulse in pulse position modulation (PPM), an effective scheme called the Differential-Pulse-Position-Width Modulation scheme (DPPM + PWM) is proposed based on the Differential pulse position modulation and Pulse Width Modulation. The symbol structure, power efficiency, bandwidth efficiency, information transmission capacity and packet error rate in a nondispersive channel are presented and compared with OOK, PPM and DPPM. Based on the given model, the analysis and stimu-lation results show that DPPM + PWM has advantages in bandwidth efficiency and information transmission capacity and it increases the length of the modulated pulse and doesn't need symbol synchronization, and can help to simplify the receiver system.