Design and characteristics of submarine optical cable

The applicability of high-power laser diodes to optical intersatellite links

“…In this case, as the antenna gain is 116.5 dBi (a = 0.8 [13]), the value of G t LG r is 40 dB, 20 dB larger than that of fiber communication. In this case, as the antenna gain is 116.5 dBi (a = 0.8 [13]), the value of G t LG r is 40 dB, 20 dB larger than that of fiber communication.…”

“…On the other hand, in the ISL system, the loss L f reaches 273.0 dB at l = 0.84 mm (which is the wavelength of the LD used in this paper) for D = 20 cm in a LEOLEO link (3 ´ 10 3 km). In this case, as the antenna gain is 116.5 dBi (a = 0.8 [13]), the value of G t LG r is 40 dB, 20 dB larger than that of fiber communication. It is found that for LDs used in ISL, an output power more than two orders of magnitude greater is needed in comparison with fiber communications.…”

“…Only LDs whose power is between several and several tens of milliwatts can operate in a single transverse mode [13]. Since the laser beam propagates over such a long distance between satellites, an output power greater than several hundreds milliwatts is required.…”

“…Today, there are several kinds of LD in optical fiber communications: AlGaAs 0.8-mm LDs are used for shorter-distance communication systems, and In-GaAsP or Multi-Quantum Well (MQW) LDs of 1.3 to 1.55 mm for longer ones. Only LDs whose power is between several and several tens of milliwatts can operate in a single transverse mode [13]. However, more output power is needed for an optical ISL.…”