提出并研究了一种应用于光纤载太赫兹波通信系统(ToF)中双级级联单边带(DSSB)调制的新方案。首先抑制载波双边带(DSB)调制产生太赫兹波;然后选择载波抑制DSB中的一个边带进行一级单边带(SSB)数据调制,在数据调制过程中再次采用基带SSB调制技术,由此产生DSSB调制。分析结果显示,对0.1 THz中频载波,数据速率为5 Gb/s的光载太赫兹信号进行100 km光纤传输,无色散补偿的误码率仅为1×10-11数量级,接收机灵敏度为-26.6 dBm。给出了单、双边带调制信号频率选择性衰落对比曲线图,有效地证明了DSB信号传输中色散衰落现象的存在以及SSB调制对于这种衰落现象的有效抑制,这些结论均证明新方案明显优于传统方案。 A new scheme of dual-stage cascaded single-sideband (DSSB) modulation for fiber-optic terahertz wave communication system (ToF) is proposed and studied. Firstly, it suppresses the modulation of carrier double-sideband (DSB) to generate terahertz wave; then selects one sideband of carrier suppression DSB to perform primary sideband (SSB) modulation and baseband SSB modulation again during data modulation. Generate DSSB modulation. The results show that for the 0.1 THz IF carrier, the optical carrier terahertz signal with the data rate of 5 Gb / s is transmitted in 100 km optical fiber. The BER without dispersion compensation is only 1 × 10-11, the receiver sensitivity is - 26.6 dBm. The frequency-selective fading comparison curves of single-band and double-sideband modulated signals are given. The existence of dispersion fading phenomenon in DSB signal transmission and the effective suppression of this fading phenomenon are validated by these two conclusions. These results prove that the new scheme is obviously superior In the traditional program.