放大自发辐射（ASE）是限制铒镱共掺光纤激光器和放大器功率提升的重要因素。通过数值计算，对单模铒镱共掺光纤放大器中的ASE进行仿真，重点模拟了光纤参数对ASE的影响，并进行提升输出功率方法的分析。通过改变抽运方式、抽运光波长、光纤放大器长度和掺杂离子的浓度等相关参数研究了ASE的影响因素。研究结果表明，反向镱离子波段ASE是影响信号光功率输出的主要因素，前向铒离子波段ASE则主要影响输出光的光谱特性。光纤参数的优选可以有效地抑制镱离子波段和铒离子波段的ASE，在保证光谱质量的同时提升信号光输出功率。

Amplified spontaneous emission (ASE) is one of the largest limitations for Er-Yb co-doped lasers and amplifiers. We perform the numerical simulation about the ASE in Er-Yb co-doped fiber amplifier and analyze possible ways to promote the output power by varying parameters of the amplifier. We study the influencing factors on ASE by varying pumping methods, wavelength of pumping light, fiber lengths and doping density. Results show that backward Yb-related ASE influences the output power mostly while the forward Er-related ASE affects the spectrum of laser. Choosing suitable parameters can decrease both Yb-related and Er-related ASE, and promote the output power with good spectrum.