就时间抖动对相位编码量子密钥分发(QKD)系统量子误码率(QBER)的影响进行了系统的分析,建立了相位编码QKD系统量子误码率和时间抖动关系的物理模型,给出了单光子脉冲的一般波形函数和量子误码率之间的关系。针对高斯脉冲分布,导出了时间抖动引起的相位编码QKD系统的量子误码率与脉冲宽度和时间抖动分布参数之间的定量关系。得出高斯分布的单光子脉冲在确定的时间抖动分布的情况下系统的量子误码率。提出了通过控制系统抖动参数和单光子脉冲宽度来减小系统量子误码率的方法。 The influence of time jitter on the quantum error rate (QBER) of QKD system is systematically analyzed. The physical model of quantum bit error rate (BER) and time jitter in QKD system is established. The relationship between the general waveform function of a single photon pulse and the quantum error rate. Aiming at the Gaussian pulse distribution, the quantitative relationship between the quantum error rate and the parameters of pulse width and time jitter distribution of phase-encoding QKD system caused by time jitter is derived. The quantum error rate of the system is obtained for a single-photon pulse of Gaussian distribution at a given time-jitter distribution. A method to reduce the quantum error rate of the system by controlling the jitter parameters and the single-photon pulse width is proposed.