Fig. 1. Diagram of EDRS system and location^[19]

Fig. 2. TESAT LCT^[12]. (a) Image of product; (b) principle diagram

Fig. 3. GEO-LEO laser links over 24 h^[20]

Fig. 4. In-orbit test results^[20]. (a) Link establishment time; (b) tracking error;(c) BER for 600 Mbps communication; (d) power consumption

Fig. 5. AOC installed in Airbus A310^[21]

Fig. 6. LCRD mission architecture^[13]

Fig. 7. Photos of LCT^[13]. (a) Optical module; (b) modem

Fig. 8. Optical ground stations （OGSs）^[13]. (a) California OGS; (b) Hawaii OGS

Fig. 9. Concept of JDRS^[15]

Fig. 10. Structural model of JDRS LCT^[15]. (a) GEO LCT; (b) LEO LCT

Fig. 11. Diagram of GEO LCT for HICALI^[17]

Fig. 12. Ground observation equipment^[17]. (a) Distributed ground station with 1 m diameter; (b) link condition analysis equipment

Fig. 13. LCT of SJ-20 satellite

Fig. 14. Schematic diagram of AO correction system for laser communication

Fig. 15. States before and after AO correction. (a) Wavefront distortion; (b) jitter of light spot

Fig. 16. ScyLight thematic lines and related technological areas^[23]

Fig. 17. WDM technical route of successor for JDRS^[26]

Fig. 18. Bidirectional distortion compensation system of NICT^[17]

Fig. 19. Laser comm modem based on PIC (NASA) ^[37]

Fig. 20. Concept map of space-based laser information network^[23]

Fig. 21. Overall system concept of HydRON^[23]