Global Voice Chat Over Short Message Service Of Beidou Navigation System

The capability of short message service (SMS) of Beidou navigation system (BDS) is an advantage over the GPS. Text-only SMS hinders the applicability of BDS. The global voice chat has been designed & tested over the BDS SMS, which can transmit voices of 2 seconds in a single 78-byte message. Field tests have been completed between two sites far apart over 2,500 km, one in the city of Xi'an and the other onboard a ship in the South China Sea. Results have shown that the voice chat over the BDS SMS is available to any subscriber even he cannot type a single word. More than 90% of interaction time is saved and authentication security is enhanced. The global voice chat is an effective supplement to the outdoor emergency communication systems nowadays.