论文部分内容阅读
通过引入一个描述掺铒光纤放大器（ＥＤＦＡ）受扰后偏离其常态程度的参数Ｘ＿ｉ，本文推导出一个不依赖于具体参数的归一化的ＥＤＦＡ增益表达式，应用该式进行分析的结果表明，以Ｘ＿ｉ作为衡量系统恢复程度的参数，具有简便易行等优点。对于ＥＤＦＡ饱和程度较浅的陆上光纤通信系统而言，系统经３ｄＢ的扰动后，光功率在３级内即可恢复到原值的９０％。扰动引起的系统误码率（ＢＥＲ）的变化，随扰动开始级数的不同而显著不同：前几级ＥＤＦＡ处开始受扰对系统ＢＥＲ的影响甚微；而后几级、特别是末级ＥＤＦＡ开始受扰则可能导致系统达不到所要求的ＢＥＲ，当ＥＤＦＡ增益比小信号增益低１０ｄＢ时，即使末级ＥＤＦＡ受到３ｄＢ扰动，ＢＥＲ仍小于１０￣（－９），系统饱和越浅，受扰动的影响就越严重，需要在实际的系统设计中认真加以考虑。
By introducing a parameter X_i that deviates from its normal state after being disturbed by an erbium-doped fiber amplifier (EDFA), a normalized EDFA gain expression that is independent of specific parameters is deduced. The results of analysis using this formula show that, X_i as a measure of the degree of system recovery parameters, with the advantages of ease. For the land-based optical fiber communication system with shallow saturation of EDFA, after the system is disturbed by 3dB, the optical power can be restored to 90% of the original value within 3 levels. The system bit error rate (BER) changes caused by the disturbance vary significantly with the number of disturbance starting stages: the first few EDFs at the beginning of the disturbance have little effect on the system BER; while the last few stages, especially the final EDFA, When disturbed, the system may not reach the required BER. When the EDFA gain is 10 dB lower than the small signal gain, the BER will be less than 10 -9 even if the final EDFA is disturbed by 3 dB. The more saturated the system, the more disturbed The more serious the impact, the need to seriously consider the actual system design.