We have designed a beaconless laser communication terminal based on intensity modulation and direct detection(IM/DD).In this terminal,a compound-axis tracking system composed of a coarse tracking loop based on a large...We have designed a beaconless laser communication terminal based on intensity modulation and direct detection(IM/DD).In this terminal,a compound-axis tracking system composed of a coarse tracking loop based on a large aperture mirror driven by a stepper motor and a fine tracking loop based on a fast steering mirror(FSM)driven by piezoelectric ceramics is used to realize wide-range and high-precision beam tracking.By optimizing the control loop delay and control parameters,the-3 d B tracking bandwidth of the system is 50 Hz,which can effectively suppress the deterioration of communication performance caused by platform micro-vibration.When the terminal operates in orbit,the tracking error(3σ)is 2.8μrad.With Reed–Solomon[RS(255,223)]error correction coding,a sensitivity of-40.5 dBm is achieved while the bit error rate(BER)is below10^(-7)at 10 Gbps.The bidirectional-link experiment has been repeated 45 times,and the results show that the acquisition success ratio is 93%.The methods proposed in this paper are analyzed and verified by the GMS-βsatellite in orbit.展开更多
文摘We have designed a beaconless laser communication terminal based on intensity modulation and direct detection(IM/DD).In this terminal,a compound-axis tracking system composed of a coarse tracking loop based on a large aperture mirror driven by a stepper motor and a fine tracking loop based on a fast steering mirror(FSM)driven by piezoelectric ceramics is used to realize wide-range and high-precision beam tracking.By optimizing the control loop delay and control parameters,the-3 d B tracking bandwidth of the system is 50 Hz,which can effectively suppress the deterioration of communication performance caused by platform micro-vibration.When the terminal operates in orbit,the tracking error(3σ)is 2.8μrad.With Reed–Solomon[RS(255,223)]error correction coding,a sensitivity of-40.5 dBm is achieved while the bit error rate(BER)is below10^(-7)at 10 Gbps.The bidirectional-link experiment has been repeated 45 times,and the results show that the acquisition success ratio is 93%.The methods proposed in this paper are analyzed and verified by the GMS-βsatellite in orbit.
