本文理论分析了掺铒光纤放大器的最佳信号波长，计算了放大器增益与信号波长、最佳信号波长与掺杂光纤长度及噪声系数与掺杂光纤长度的关系，指出了最佳信号波长为１．５５５μｍ； This paper theoretically analyzes the best signal wavelength of the EDFA and calculates the relationship between the gain of the amplifier and the signal wavelength, the best signal wavelength, the length of the doped fiber, the noise figure and the length of the doped fiber. The optimal signal wavelength is 1 .555 μm;