四进制差分偏振移位键控通信

Four Differential Polarization Shift Keying

提出一种在电域进行四进制差分编码的偏振移位键控通信系统,可克服单模光纤中光偏振态随机扰动对接收效果的影响.在光发射机中,通过差分编码使前后两个符号周期偏振状态差异与差分编码器的输入之间建立对应关系.在接收端,提取前后两个符号周期内光的斯托克斯矢量并将二者点乘,就能提取两个符号周期内偏振状态的差异,恢复发送序列.即使在不用动态偏振控制器情况下,点乘运算也能有效消除光偏振状态的随机扰动对系统性能的影响.

In this paPer, optical communication using quaternary differential polarization shift keying is proposed, which is immune to random fluctuation in the state of polarization （SOP） of the optical signals propagating through a single mode fiber. Relationship is established in the transmitter using differential coding between the difference in SOPs of the optical signals in consecutive symbol periods and the input symbol of the differential encoder. In the receiver, Stokes vectors are extracted from the optical signals in two consecutive symbol periods. Dot product of the two vectors is then obtained so that the transmitted sequence recovered.The dot multiplication can effectively eliminate the effect of random fluctuation in the SOPs of optical signals on the performance of communication system.