PERFORMANCE ANALYSIS OF CHIP-ASYNCHRONOUS COHERENT TIME-SPREADING OPTICAL CDMA SYSTEM

• 来源期刊: 光电子快报(英文版)
• 学科: 工学
• 年，卷（期）: 2009,（1）
• 页码范围: 30-33
• 页数: 4页
• 分类号: TN914.53
• 语种: 中文

摘要

Multiple-access interference(MAI) and beat noise(BN) in chip-asynchronous coherent time-spreading OCDMA system are evaluated by the aperiodic cross-correlation function of up-sampled sequence.Relationship between the mean intensity of aperiodic cross-correlation and MAI and BN is deduced,and then the relationship between BER and mean intensity of aperiodic cross-correlation is discussed.For 127-long gold sequence,mean BER performance of chip-asynchronous coherent time-spreading OCDMA is derived and compared with that of the chip-synchronous system.It can be shown that the chip-synchronous assumption provides a performance upper limit.For realistic asynchronous coherent time-spreading OCDMA system,BER will reduce by about one order of magnitude.