EDFA Anti-Irradiation Schemes for Inter-Satellite Optical DPSK Communication Systems

The uprising of rare-earth-doped fiber amplifier technology provides an effective solution to signal power compensation for interstellar optical communication systems, but significant signal power attenuation induced by spatial irradiation has ever been a significant issue to be resolved in practical applications. In order to explore the impact of radiation on the performances of high-speed differential phase shift keying (DPSK) satellite communication systems using EDFA preamplification technique, the irradiation effect on output central wavelength, half width, and noise figure (
NF
) of EDFA has been studied. Different anti-irradiation schemes employing Co
⁶⁰
radiation sources with a total radiation dose of up to 300 krad are compared from experimental perspective to optimize the anti-irradiation scheme. Radiation-induced attenuation (RIA) as well as increase in
NF
of the EDFA is considered in our simulation model, by which the limitations of the physical shielding scheme could be clarified and quantitatively evaluated
.
We conclude that compared to the RIA effect, the increase in noise figure plays a major role in the degradation of communication systems. In addition, according to simulation results of two high-speed DPSK systems, some anti-irradiation schemes are proposed as recommendations for future applications of EDFA-assisted optical systems under radiation exposure environments.