Zhoushi Yao

Influence on the Bit Error Ratio of the Optical Satellite Communication System under Space Radiation Environment

To improve the space anti-radiation performance of the optical satellite communication system, the research of the influence on its system bit error ratio(BER) under space radiation environment was developed. The radiation-induced BER model was established, based on which the BER numerical calculations after the radiation damage of either optical source or optical detector were developed. The calculation results have proved that both γ and proton radiations can degrade the system BER by several levels, some suitable radiation shielding equipments are further needed.

Compensation mechanism of polarization-independent reflection structure based on two magneto-optical crystals and two mirrors

We provide, to our knowledge, the first experimental demonstration of polarization-independent reflection structure, which is based on two magneto-optical crystals with 90° rotatory angles and two mirrors without depolarization. The experiment shows that the polarization fidelity achieved about 99.98%. We also find out that even the rotatory angles of magneto-optical crystals are not 90°, when the two rotatory angles are near to 90°, the closer they are, the higher polarization fidelity is. This characteristic can be very important and useful for engineering implementation. It is also approved in theory and experiment.

Analysis of charge transfer inefficiency of CCD equipment under proton radiation

The charge coupled device(CCD) is the key component of beacon light subsystem in optical satellite communication system. The influences of space radiation environment on CCDs charge transfer efficiency(CTE) and its dark current are theoretically analyzed. Based on the analysis the induced CTE degradations under some typical operation temperatures and particle fluences are numerically calculated. The calculation results have proved that adding shielding layers and temperature controlling unit are both the efficient ways to improve the radiation hardness of optical satellite communication system.