针对无线光通信系统中反向差分脉冲位置调制(RDPPM)功率利用率较低以及差错性能较差等问题，结合反向脉冲宽度调制方式(RPWM)与RDPPM，提出了一种新型组合调制方式，即反向差分脉冲位置宽度调制(RDPPWM)。研究分析了RDPPWM 的符号结构、平均发射功率、带宽需求以及在理想加性高斯白噪声(AWGN)干扰下的误包率，并与开关键控(OOK)、RDPPM、RPWM 等调制方式进行了比较。仿真结果表明，RDPPWM 可以获得较高的功率利用率，增加了信道容量，降低了带宽需求，且不需要符号同步；在相同信号接收功率-28 dBm 的条件下，RDPPM 的误包率是2.2×10-8，但是RDPPWM 的误包率却可以降低至2.6×10-12。故RDPPWM 为无线光通信的调制技术提供了一种新的选择。

In order to solve the problems of lower power efficiency and bad packet error rate in reverse differential pulse position modulation scheme for wireless optical communication, a new hybrid modulation scheme called the reverse differential pulse position width modulation (RDPPWM) is proposed, based on reverse differential pulse position modulation (RDPPM) and reverse pulse width modulation (RPWM). The symbol structure, average transmission power and bandwidth requirement of RDPPWM and its packet rate error in additive white Gaussian noise (AWGN) channel are presented and compared with on-off keying (OOK), RDPPM and RPWM. The stimulation results show that RDPPWM has advantages in power efficiency and channel capacity, and it can decrease bandwidth requirement and doesn′t need symbol synchronization. The packet error rate of RDPPWM can drop to 2.6×10-12 while that of RDPPM is 2.2×10-8 when the same signal power is -28 dBm. Therefore, these considerations make RDPPWM a favorable candidate to select as the modulation scheme in wireless optical communication.