The high-quality generation and precise phase synchronization of high-speed modulated baseband signals are key technologies of space optical communication ranging system.Traditional approaches relying on FPGA or Digital Signal Processor(DSP)and high-speed Digital to Analog Convertor(DAC)technology often suffer from limited phase synchronization accuracy and high hardware complexity.A method for high-speed optical communication baseband signal generation and phase synchronization is proposed and a phase-locked dynamic control loop is designed in this paper.By dynamically adjusting the phase of the high-speed signal transmission clock in real time,the deterministic relationship between the I/Q high-speed baseband signal phase and the external reference clock phase can be achieved.The experimental results demonstrate impressive performance metrics:When the code rate of the Quadrature Phase Shift Keying(QPSK)optical modulated signal is 5 Gbit/s,the phase synchronization accuracy is less than 2 ps and the Error Vector Magnitude(EVM)is less than 8％;the bit error rate is 10-7 at a 5 Gbit/s optical communication rate,the receiver sensitivity is better than-47 dBm,and the ranging accuracy is better than 2 mm.Compared with traditional methods,both sensitivity and ranging accuracy are significantly improved.
关键词
光通信测距/相位同步/闭环动态控制/误差矢量幅度
Key words
Optical communication ranging/Phase synchronization/Closed-loop dynamic control/Error Vector Magnitude(EVM)
维普
万方数据