Method, system and medium for satellite mobile communication random access with time advance compensation

Abstract

The invention provides a time advance compensation satellite mobile communication random access method and system and a medium, and the method comprises the steps: a downlink broadcast sending step: obtaining a cell formed by a wave beam of a satellite on the ground, obtaining the minimum TA in the cell, recording the minimum TA as TAmin, and enabling the satellite to send satellite position information and TAmin in the downlink broadcast; And a transmission delay calculation step: enabling the UE to receive the downlink broadcast, obtaining the satellite position information and the TAmin according to the received downlink broadcast, and calculating the difference value TAdiff of the TA estimated by the UE per se relative to the TAmin. In the random access process of the satellite, the transmission time delay is estimated in advance at the UE side and compensation is performed when the PRACH is sent, so that the problem of high time cost caused by long time delay in the random accessof the satellite is solved, and the consumption of uplink resources by the PRACH is greatly reduced.

Description

Technical field [0001] The present invention relates to the technical field of satellite communication, in particular to a method, system and medium for random access of satellite mobile communication with time advance compensation. Background technique [0002] Satellite mobile communication has gradually attracted the attention of the industry. Most companies and communication organizations believe that the integration of satellite and ground network infrastructure has huge market potential. In 3GPP Release 14, the importance of satellite communication in 5G has been confirmed, and in Release 15, 5G technology is used for satellite communication research. As part of the 5G access technology, satellites are especially suitable for serving critical missions and industrial applications in ubiquitous coverage. [0003] The wireless access provided by satellites can help promote the launch of 5G services in unserved or under-served areas to make up for the lack of ground network cove...

AI Technical Summary

Problems solved by technology

[0027] The existing LTE random access process does not pre-estimate its own timing advance when the user initiates access. All TA calculations are performed at the base station. When this method is used for satellite access, the PRACH time overhead will be unbearable.

Due to the long transmission distance of GEO and LEO satellites, large cell radius, and large delay difference, the time overhead of PRACH using the existing LTE protocol is much higher than that of the ground access system, and the existing random access protocol cannot support satellite scenarios. through a certain mechanism

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