基于沃尔泰拉理论的集总光纤非线性噪声补偿

通过沃尔泰拉(Volterra)级数理论求得了非线性薛定谔方程(NLSE)的半解析解,在考虑光纤损耗、色散及非线性效应的情况下,推出了长距离在线级联掺铒光纤放大器(EDFA)光纤通信系统中信号和自发辐射噪声(ASE)之间耦合串扰的半解析表达式,得到了多跨距传输接收端输出信号和发射端输入信号之间的关系式.根据维纳(Wiener)滤波理论的时域滤波原理,在多跨距传输系统接收端设计了对非线性乘性噪声有滤波作用的维纳滤波器,并对预集总色散补偿、后集总色散补偿、分布链路色散补偿系统及一对三"跨距成比例平移对称的色散非线性同步补偿系统进行了仿真模拟研究.结果表明了提出的设计思路及方法的可行性,为进一步提高传输距离增大入纤功率提供了新的思路.

Lumped Fiber Nonlinear Noise Compensation Based on Volterra Theory

The semi-analytical solution of nonlinear Schrdinger equation (NLSE) is obtained by Volterra series theory, and the semi-analytical expression of coupling crosstalk between the useful pulses and amplified spontaneous emission (ASE) induced by the combined effects of fiber loss, dispersions and nonlinearities is derived in a high-speed long-haul fiber-optic system, which is made up of multi-span with each including a transmission fiber and an erbium doped fiber amplifier (EDFA), and the relational expression between the output signal at the receiver and the input signal at the transmitter of multi-span transmission is also obtained. Besed on the time-domain filtering method of Wiener filtering, a Wiener filter is designed at the receiver to filter the multiplicative crosstalk noise mentioned above. Its applications in pre-, post-lumped and distributed dispersion compensation system, as well as “one-for-three” compensation fiber spans transmission lines with scaled translational symmetry are proved feasible by numerical simulations, which provide a novel solution to improve fiber input power and nonlinear channel capacity.