Design And Implementation Of Vehcile Audio And Video Transmission Terminal Based On 4G

With the rapid development of global economy, private cars and public transport are increasing. Although the growth of vehicles can significantly facilitate public trips, the traffic pressure that comes along inevitably increases and different levels of traffic congestions can be found across the country. No matter from the prospective of real-time traffic monitoring or quick report for the traffic accident, the demand of stable and reliable vehicle monitoring terminals is increasing. This paper designs a vehicle audio and video transmission terminal(vehicle terminal for short) applied to highway, to make up the transmit-ability deficiency of vehicle terminals on the market, and adapt to the current network environment. This paper illustrates the design of vehicle terminal from the terms of hardware and software and the main works are as follows:(1) This paper introduces the development and status quo of vehicle terminals, and analyzes the advantages and disadvantages of the existing vehicle terminals. Some key technologies of vehicle terminals are introduced. The TMS320DM365 of TI is selected as the core processor and FDD- LTE networks of Unicom is selected as the mobile transmission networks of vehicle terminal based on the project demand.(2) Smallest system and peripheral circuit are designed with the TMS320DM365 as the core processor. The designs of audio and video modules are introduced in detail in this paper. For the audio part, the FM1188 chip of American Forte Media is used as the echo cancellation chip, and TVLAIC3101 chip of TI is used as the sound card. For the video part, TVP5151 chip of TI is used as A/D conversion of the analog video signal, and H.264 format is used for video compression coding.(3) Vehicle terminal software is designed based on Linux embedded system. The designs of audio and 4G parts are illustrated in detail in this paper. The sound card is designed by using ALSA architecture, and audio data is coded by using G.711 coding compression. The PPPD is used to dial-up access for the 4G part, and offline replay mechanism is designed against 4G drop phenomenon.(4) Vehicle terminal audio functions and videofunctions are tested, and the testing results are analyzed and concluded.