摘要
为了研究信道编码技术对无线光通信副载波系统差错性能的影响,基于无线光通信链路噪声特性,建立了大气信道等效数学模型。采用低密度奇偶校验(LDPC)码作为信道编码方式引入无线光通信,在不同光强闪烁指数下对基于副载波相移键控调制无线光通信系统进行了差错性能仿真,比较分析了LDPC编码前后副载波调制系统的误比特率,并对二相相移键控及四相相移键控两种系统进行了对比。结果表明,副载波二相相移键控调制系统的差错性能优于四相相移键控系统,同时LDPC码在弱湍流信道具有优越的纠错能力,可以获得比未编码系统较高的编码增益,在无线光通信领域具有一定的应用价值。
In order to study the effect of channel code technology on bit error rate （BER） performance of wireless optical communication subearrier systems, based on noise characteristics of wireless optical communication, atmospheric channel model was found. Low density parity check （ LDPC ） code was introduced as the channel code in wireless optical communication, the error rate of wireless optical communication using subcarrier modulation was simulated under different scintiUation distribution, and the BER performance between LDPC code coded and uneoded systems of binary phase shift keying （BPSK） and quaternary phase shift keying（QPSK） system was compared. The simulation results show that error performance of the BPSK system is better than that of QPSK system, and LDPC code has excellent error correction capabilities with a larger coding gain, and has some applicable values in the field of wireless optical communication.
出处
《激光技术》
CAS
CSCD
北大核心
2011年第3期388-390,402,共4页
Laser Technology
基金
国家自然科学基金资助项目(60977054)
国防重点实验室基金资助项目(9140C3601010701)
军队八六三创新计划资助项目(2008AAJ159)
西安理工大学青年科学研究计划资助项目(105-210816)
西安理工大学科技创新科学研究资助项目(105-211014)
关键词
光通信
低密度奇偶校验码
副载波相移键控
误比特率
性能
optical communication
low density parity check code
subcarrier phase shift keying
bit error rate
performance
