论文部分内容阅读
S.D.Personick计算数字光通信接收机灵敏度、APD的最佳倍增因子及判决电平,是以接收机输入端光脉冲波形作为计算的出发点,并以光脉冲波形为矩形、高斯形及指数形计算出基本参数.作为计算灵敏度等指标的参数。但在实用上,接收机输入端的光脉冲波形与上述三种有较大的差别,给计算带来困难。本文提出以易于确定的发送端光脉冲波形及光纤展宽参σ＇作为计算出发点,并假定光纤对光脉冲的响应为高斯函数。据此计算出基本参数,从而计算出接收机灵敏度及APD最佳倍增因子与光纤特性参数σ＇的关系,并画出曲线。由于σ＇与光纤长度ι的α次方成正比,即σ＇∞ι~α,故横坐标又可转换成长度ι,使便于用图解法。 本文仍用文献[1]提出的计算方法,只是计算的出发点不同。
SDPersonick calculate the receiver sensitivity of digital optical communications, APD the best multiplication factor and the decision level, the receiver input pulse waveform as a starting point for the calculation, and the light pulse waveform is rectangular, Gaussian and exponential calculated Basic parameters as parameters for calculating sensitivity and other indicators. However, in practicality, there is a big difference between the light pulse waveform at the input end of the receiver and the above-mentioned three types, which brings difficulties to the calculation. In this paper, a simple and easy to determine the transmitter pulse waveform and fiber stretch parameter σ ’as the starting point of calculation, and assume that the optical fiber response to optical pulses Gaussian function. Based on this calculation of the basic parameters to calculate the receiver sensitivity and APD best multiplication factor and fiber characteristics of the parameters of the relationship between σ ’and draw the curve. Since σ ’is proportional to the α-th power of the optical fiber length ι, that is, σ’∞ι ~ α, the abscissa can be converted into the length ι, which facilitates the use of graphic method. In this paper, the calculation method proposed in [1] is still used, but the calculation starting point is different.