时域相位光码分多址系统性能分析  

Performance Analysis of Temporal Phase Optical Code-Division Multiple Access System

作　　者：朱英勋[1,2] 王荣[1] 丁晓光 蒲涛[1] 

机构地区：[1]解放军理工大学通信工程学院,江苏南京210007 [2]军训器材研究所,辽宁沈阳110035

出　　处：《光学学报》2008年第10期1874-1882,共9页Acta Optica Sinica

基　　金：国家自然科学基金(60502003)资助课题

摘　　要：给出了时域相位光码分多址系统(OCDMA)的噪声模型,提出了由码间串扰(ISI)所引起的自差拍噪声(SB)概念。利用鞍点近似法分析了多址干扰(MAI)、码间串扰、自差拍等噪声对系统性能的影响,给出了系统误码率公式。对最佳门限接收系统以及采用光硬件限幅器的系统性能进行了仿真研究,表明"1"码的误判概率是影响系统的决定性因素,也是开关键控(OOK)系统难以克服的主要问题。最后给出一种采用双编/解码器平衡检测系统的原理框图,分析其性能,并与传统OOK系统比较,结果表明其性能有较大的提高。The noise model of temporal phase optical code-division multiple access （OCDMA） system is given. The concept of self beat noise induced by inter symbol interference （ISI） is proposed. The impact of multiple access interference（MAI）, ISI and self beat noise on system performance is analyzed.by using saddle-point approximation and the bit error rate（BER） expression of the system is presented. Simulations on the systems with optimal threshold and optical hard limiter show that the error probability of symbol ＂1＂ is the key factor to the system performance and it is also the main matter for on/off keying（OOK） system to overcome. A balance detection system with two en/ decoders is presented and its performance is analyzed and compared with traditional OOK system. Results show its superior performance to the traditional one.

关 键 词：光通信 光码分多址 码间串扰 多址干扰 差拍噪声 鞍点近似 

分 类 号：TN929.11[电子电信—通信与信息系统]