基于SSFBG的±π/2和0/π相移编码的安全性比较

Security Comparison of ± π/2 and 0 / π Phase-shifted Superstructured Fiber Bragg Grating Encoding

分别采用0/π和±π/2相移的方式对光脉冲信号进行了编码,并比较了基于超结构光纤光栅的0/π和±π/2两种相移编码方式的安全性,通过研究分析两编码器所生成的编码波形来评估各自的安全性。结果表明,0/π相移编码器生成的编码波形中存在明显的凹陷,光学码信息易被窃取,安全性低;而±π/2相移编码器生成的编码波形能隐秘地将光学码信息隐藏于编码波形中,大幅改善了编码安全性,提高了通信安全。

In this paper,0 / π-phase-shifted SSFBG（ 0 / π-SSFBG） and the ± π /2-phase-shifter SSFBG（ ± π/2-SSFBG） are used to encode the optical pulse signal. A comparison is made of the security performance of the 0 / π-SSFBG and the ± π /2-SSFBG. We evaluate the security performance by the investigation of the encoded waveforms of both encoders. The existence of dips in the waveform encoded by 0 / π-SSFBG allows eavesdroppers to extract code sequence straightforwardly. Nevertheless,the ± π /2 SSFBG based encoder improves the security by concealing the code information in the encoded waveform.