降低频谱编码光码分多址系统干扰的实验研究

Reductions of Multiple Access Interference and Beat Noise in Optical CDMA Communication with Bragg Grating Arrays

讨论了频谱编码光码分多址系统的多址干扰和噪声特性.选用m序列为地址码,利用可调谐布喇格光栅阵列实现了频谱编码,实验研究了在基于布喇格光栅编解码的光码分多址系统中可以利用平衡检测接收的方法消除多址干扰,但光源的频谱不平坦性,编解码器的不一致性都会降低平衡检测克服多址干扰的效果.讨论了差拍噪声对系统性能的影响,并提出了采用互补分配波长的新的编码方式,与原有系统相比,用户容量增大一倍,同时可以降低差拍噪声,使系统输出端噪声影响进一步降低.

The Multiple Access Interference(MAI) and Beat Noise in OCDMA system were investigated. The Balanced photo detectors method is proved to reduce MAI effectively by experiments. It is observed that the nonideal Fiber Bragg Grating(FBG) encoder , the difference between reflect ratio and transmit ratio of the FBG will deteriorate MAI by experiments. A new wavelength allocation based on compensation is used in code design .the new code can reduce beat noise and double the simultaneous uses numbers.