为了研究量子通信信令系统, 实现多用户之间进行通信, 提出了一种量子信令的偏振态差分相位编码方案, 阐述了编码过程.发送方使用光子的不同偏振态来表示不同的信令, 然后对光子进行相位调制, 通过前后两个光脉冲的相位差进行量子信令编码.接收方根据两个光脉冲在光合束器处发生干涉, 由于相位差不同可以被不同的检测器检测到而得到0或1信号完成解码.根据高斯脉冲分布, 导出了光子传输过程中由于脉冲延迟引起的差分相位编码系统的量子误码率与脉冲宽度以及延迟时间分布参量之间的定量关系, 推出高斯分布的单光子脉冲在确定的时间抖动分布情况下系统的量子误码率.对量子信令编码效率和误码率进行分析并仿真, 结果表明本文提出的编码方案可以达到75%编码效率, 能够满足量子移动通信的需要.

In order to study the quantum communication signaling system and realize quantum communication between multiple users, a kind of differential phase encoding scheme for the polarization state of quantum signaling is proposed, and details of the encoding process are described. The sender uses polarization states of different photons to represent different signalings, and then implements phase modulation for the photons and encodes the quantum signaling based on the phase difference between the impulses before and affter encoding. In order to complete the decoding, two optical pulses occur interference at the beam splitter. The signal 0 or 1 can be detected by different detectors according to their phase difference. According to the Gaussian pulse distribution, quantitative relationship amongthe quantum bit error rate caused by the pulse delay to differential phase of encoding system, pulse width and delay time in photonic transmission process are enduced.Besides, quantum bit error rate of single-photon pulsesdistribution of Gaussian is calculated in determined timing jitter. Finally, quantum signaling encoded efficiency and bit error rate are analyzed and simulated.The results show that the encoded efficiency of proposed coding scheme can reach 75% that can satisfy the needs of quantum mobile communication.