论文部分内容阅读
实用被动调制量子密钥分发系统中分束器存在波长依赖性,窃听者据此攻击分束器,以获取密钥信息并且不被发现,而且光纤中存在瑞利散射导致误码率增大。文中提出波分复用器方案来保障量子密钥分发的安全性,并且通过双波长交叉传递来降低误码率。方案中借助于波分复用器将不同波长的光子进行分离,只对部分波长的光子进行偏振测量,Alice和Bob可以通过公共信道分析误码率和收益,得出是否存在窃听者。
The beam splitter in practical passive modulation quantum key distribution system has the wavelength dependence, so the eavesdropper attacks the beam splitter accordingly to obtain the key information and is not found, and Rayleigh scattering in the optical fiber results in an increase of the bit error rate. In this paper, the WDM scheme is proposed to ensure the security of quantum key distribution, and the bit error rate is reduced by two-wavelength cross-transmission. In this scheme, photons with different wavelengths are separated by means of wavelength division multiplexer, and polarizations of photons of some wavelengths are only measured. Alice and Bob can analyze the bit error rate and gain through public channel to find out if there exists eavesdropper.