BeiDou Short Message Service

The Beidou Satellite Navigation System is a global satellite navigation system independently developed by China. Short message is a unique feature that allows users to transmit information to others in both directions through Beidou satellites without ground communication network coverage. This unique feature is different from other positioning satellites and has unique advantages, especially suitable for emergency search and rescue and maritime communication fields.

The unit is designed for unsupervised public use: controls are recessed or shielded, moving parts are enclosed, and the interface is operable by a child of about six with no instruction. Where a screen is used, the language can be switched without changing the hardware, and the content can be replaced on site.

The Beidou short message communication is the biggest difference and most prominent advantage of the Beidou system compared to the other three major satellite navigation systems. Beidou short message originated from Beidou-1. Since 2003, Beidou has been providing short message communication services to users based on the RDSS system since Beidou-1. Beidou-2 still inherits this system and service. On the basis of being compatible with the RDSS system, Beidou-3 uses three GEO satellites and adopts the generalized RDSS system and RNSS+short message communication system to upgrade its short message communication services. It can also achieve global short message communication through inter satellite links. The capacity of short messages in the Beidou region has expanded by more than 8 times, from a maximum of 120 Chinese characters to a maximum of 1000 Chinese characters. Through advanced high compression ratio speech encoding and decoding technology, point-to-point continuous voice intercom between users can be achieved, with a maximum transmission time of 31 seconds of speech.