Physical layer protocol method suitable for satellite-ground laser communication

Abstract

The invention provides a physical layer protocol method suitable for satellite-ground laser communication, which comprises the following steps of: caching service data: setting a service data cache region, and when a data storage space exists in the service cache region, performing a cache request on satellite load data of a downlink or station control equipment service data of an uplink so as to perform data caching; baseband framing: when the data length of the service data cache region is greater than a preset length DFL, taking data of which the length is DFL from the data cache region, and performing baseband frame framing to form a service baseband frame; frame multiplexing: when the data length of the service data cache region is smaller than a preset length DFL, filling a virtual frame, and selecting a service baseband frame and the virtual frame for output through frame multiplexing; scrambling the baseband frame; performing forward coding; framing the plurality of coding frames to form a long physical frame; interleaving the formed long physical frame; adding a physical frame header: adding the physical frame header to the interleaved physical frame; adding a pilot frequency block; scrambling the physical frame; and electro-optical modulation.

Description

technical field [0001] The invention relates to the technical field of wireless laser communication, in particular to a physical layer protocol method suitable for satellite-ground laser communication. Background technique [0002] With the rapid development of remote sensing technology, the number of satellite payloads and the resolution of payloads have been greatly improved, and the amount of data generated by them has increased geometrically. Therefore, the demand for high-speed satellite-ground data transmission has become increasingly urgent. At present, microwave-based satellite-to-ground data transmission is limited by the frequency band bandwidth and the power consumption, volume, weight, and heat dissipation of the data transmission terminal. Whether it is using a microwave frequency band with a higher frequency such as ka or using high-order modulation, VCM and other modulation It is difficult for any technology to meet the high-speed downloading requirements of m...

AI Technical Summary

Problems solved by technology

Since the atmosphere is dynamically changing in real time, the refractive index of the atmosphere fluctuates randomly. This turbulent effect further changes the random variation of the light field of the beam. Macroscopically, it is manifested as the degradation of the spatial coherence of the light field, the fluctuation of the beam drift, and the fluctuation of the arrival angle; The aerosol in the atmospheric channel absorbs and scatters the laser transmission and the intensity of the signal light flickers caused by atmospheric turbulence, which will seriously reduce the signal light power, resulting in the deterioration of the beam quality of the signal light at the receiving end and the reduction of the signal-to-noise ratio of the received signal. Thereby reducing the communication performance of the satellite-ground laser communication system and the reliability of the communication link

In addition to extreme weather conditions such as rain, clouds, and fog, atmospheric turbulence, atmospheric scattering, and atmospheric absorption under good weather conditions will affect the quality of satellite-to-ground laser beams, thereby affecting satellite-to-ground laser communication

[0005] It can be seen that the channel of satellite-to-ground laser communication is significantly different from the traditional microwave channel, and the influence of laser channel on communication is worse than that of microwave channel. The traditional physical layer protocol of satellite-to-ground microwave communication can no longer meet the needs of satellite-to-ground laser communication.

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