The Design And Implementation Of Tiantong Communication Terminal Based On Android Platform

Satellite communication system demonstrates its unique advantages in the case of geographical restriction and natural disaster.The first satellite of Tiantong-1 launched is the significance of a milestone of Chinese` satellite communication.It is extremely urgent to develop the products of the Tiantong communication terminal.Nowadays,smart OS is widespread on communication terminals.So a Tiantong terminal equipped with smart OS meets the trend of development.And Android system stands out by the market tests and the property of opening source code creates increasing numbers customizded OS.The core function of mobile terminals is the phone function,named Telephony on Android.And it is the key on developing smart OS with its extent and contents,complexity and relevance with hardware.So do researches on the theories of Telephony,can we improve the product` competitiveness by solving the problem during the customizing the OS and improving the performance and stability.When designing the Telephony on Android,variety of Modem should be covered to control the activity,get the modem and network state.For these functions,a new layer,RIL(Radio Interface Layer),is added to uniform the hardware interface.This paper first introduces the background and researches of Tiantong communication system at home and abroad.Then we explains technique on Tiantong terminals,including Android system architecture and AT command,focusing on how RIL run and the key parts of RIL.After that,the detail scheme of LD_HWA RIL rises with analyzing the AT commands on Tiantiong Modem and the communication protocols and realizing the voice communication and message.Last but not the least,some experiments are made on the custom OS for testing the voice communication and message.