基于开关键控调制的光载太赫兹正交相移键控信号产生  

Generation of Terahertz Quadrature Phase Shift Keying Signals over Fiber with On-Off-Keying Modulation

作　　者：杨雄伟 赵峰 Yang Xiongwei;Zhao Feng(School of Communications and Information Engineering,Xi’an University of Posts&Telecommunications,Xi'an,Shaanxi 710121,China;School of Electronic Engineering,Xi’an University of Posts&Telecommunications,Xi'an,Shaanxi 710121,China)

机构地区：[1]西安邮电大学通信与信息工程学院,陕西西安710121 [2]西安邮电大学电子工程学院,陕西西安710121

出　　处：《光学学报》2022年第8期53-60,共8页Acta Optica Sinica

基　　金：国家自然科学基金(61875164);陕西省创新能力支撑计划(2021TD-09)。

摘　　要：提出了一种基于开关键控(OOK)调制的光载太赫兹正交相移键控(QPSK)信号产生方案。基于双平行马赫-曾德尔调制器产生了一对光学八倍频边带信号,利用两个强度调制器分别将两路独立的OOK基带信号调制到八倍频边带的两个偏振态上,对两路偏振信号进行相位和幅度调整后再进行叠加,叠加后的光信号经过功率放大和光纤传输后在终端实现了光电转换,从而生成了太赫兹QPSK信号。在VPI仿真环境下,分别验证了80,240,400 GHz信号的传输性能。结果表明,生成的一个波特率为20 GBuad、频率为400 GHz的QPSK信号通过40 km的零色散位移光纤传输后,其误码率低于前向纠错码的阈值(3.8×10^(-3))。该方案具有无需预编码技术和数模转换器的特点,降低了信号处理的复杂度和系统成本。A generation scheme for terahertz(THz)quadrature phase shift keying(QPSK)signals over fiber based on on-off-keying(OOK)modulation is proposed.A pair of optical octave sideband signals is generated by a dual-parallel Mach-Zehnder modulator(DP-MZM),and two independent OOK baseband signals are modulated to two polarization states of the octave sideband signals by two intensity modulators(IMs).The two polarization signals are superimposed after phase and amplitude adjustment,and the superimposed optical signal undergoes photoelectric conversion at the terminal after power amplification and optical fiber transmission.THz QPSK signals are thereby generated.In the VPI simulation environment,the transmission performances of 80,240,and 400 GHz signals are verified.The results show that the bit error rate(BER)of a QPSK signal with a baud rate of 20 GBuad and a frequency of 400 GHz generated by the proposed scheme is below the forward-error-correction threshold(3.8×10^(-3))after the signal is transmitted over a 40 km zero dispersion shifted fiber(DSF).Our proposed scheme,with no need for pre-coding or a digital-to-analog converter,reduces the complexity of signal processing and system cost.

关 键 词：光通信 光载无线通信 太赫兹波段 矢量信号 正交相移键控 强度调制 

分 类 号：TN928[电子电信—通信与信息系统]