摘要
调制与解调是无线光通信中的一项关键技术。目前的无线光通信系统大多设计为光强度调制/直接检测(IM/DD)系统。开关键控(OOK)作为最早的调制方式由于易于实现而被广泛使用。但OOK调制功率效率和带宽利用率有限,易受大气噪声影响。为了进一步提高数据传输效率,提出了脉冲位置调制(PPM)技术,它具有较高的平均功率效率,较强的抗干扰能力,能够较好地满足信号传输要求。通过使用QuartusII12.0软件,编写Verilog代码并反复调试,实现了4-PPM设计。
Modulation and demodulation are key technologies in optical wireless communication system. In modem times, the optical wireless communication system is almost design of intensity modulation with direct detection (IM/DD) system. OOK, as the earliest modulation scheme, is used widely because it' s easily implemented. But OOK has a limitation of power efficiency and bandwidth utility and is easily influenced by the atmosphere noise. In order to improve the data-transmission efficiency, the technology of pulse position modulation (PPM) is proposed, it has higher average power efficiency and strong anti- interference ability which can satisfy the requirement of data-transmission. With the use of QuartusII 12.0 software and Verilog code, after the repeated testing and experiments, the 4-PPM design is implemented.
出处
《信息技术》
2015年第2期151-154,共4页
Information Technology
关键词
调制解调
无线光通信
PPM
modulation and demodulation
optical wireless communication
PPM