Research Progress on Overcoming the Atmospheric Turbulence Effect in Satellite-to-Ground Laser Communication

Abstract

The key problem in the satellite-to-ground laser communication is primarily to mitigate the effect of atmospheric turbulence. After propagating through the atmosphere with a long distance, the wave-front distortion of signal light brings about the degradation of bit error rate (BER). The experimental development of the satelliteto-ground laser communication based on the domestic and abroad research progress is described. Some effective methods and discusses to overcome the turbulence effect on the high rate communication are presented. Finally, coherent detection technology based on interference principle and differentical phase shift keying (DPSK) modulation is emphatically analyzed in the phase demodulation, and the advantages are summarized. It is predictable that this technology will become more practical and play an important role in its application areas.

Phase Alignment of an Array Optical Telescope System Using Balanced Detection

“…Mach Zehnder Modulator (MZM) excels at modulating light intensity and phase because of a characteristic of wavelength independence. It is capable of high-data-rate modulation above 40 Gbps, which has become the basis for many advanced optical modulation formats [ 4 ]. Half-bit-rate NRZ-DPSK wave pattern was generated through the first modulator.…”

“…The experimental data show that the signal-to-noise ratio approaches the quantum limit with the common-mode noise suppressed [ 3 ]. Xiaoping Ma et al proposed that the turbulence effect can be well suppressed in binary phase shift keying (BPSK) and differential phase shift keying (DPSK) modulation [ 4 , 5 ]. DPSK stores the phase information in the relative phase of adjacent symbols.…”