Research On The Characteristics Of High Speed Space Laser Transmission

Nowadays research and exploration in aerospace field is one of focus of the world.Long distance communication technology which is suitable for aerospace field is also a research hotspot.High speed communication technology between platforms such as satellite-to-ground and satellite-to-aircraft becomes an urgent need.Space laser communication receives increasing attention from all around the world due to its advantages of high transmission rate,large available spectrum,good security and anti-jamming ability.It also has a solid foundation with the development and maturity of tracking and pointing technology,optical antenna processing technology,high power semiconductor laser technology,modulation and detection technology and coding technology.Moreover,because of wavelength division multiplexing technology,space laser communication has a broader application prospect.In this paper,characteristics of high speed space laser transmission are studied.A variety of space communication systems with intensity modulation/direct detection(IM/DD)and quadrature phase-shift keying(QPSK)are designed,simulated and tested.Dense wavelength division multiplexing(DWDM)technology is also used in these communication systems.And the distance of atmosphere transmission is about 1km.Based on experiment results,the transmission characteristics are analyzed.The research parts can be mainly summarized as flowing points:1.The high speed IM/DD space laser communication system is studied.The transmission rate can reach 10Gbit/s.The Q-factor is over 4.35.And Q-factor decreases with the increase of communication rate.2.The high speed QPSK space laser communication system is studied with the transmission rate of 10Gbit/s.While the bit error rate is 10-3,the optical receiving power is-22.92 dBm.3.The DWDM high speed IM/DD space laser communication system is studied.The transmission rate can reach 20Gbit/s,and the Q-factor is over 5 in both channels.4.The DWDM high speed QPSK space laser communication system is studied with the transmission rate of 30Gbit/s.While the bit error rate is 10-3,the optical receiving power is below-20 dBm in each of the three channels.