本文介绍了一种新的基于无线自组网的嵌入式车载系统，有别于传统的车载系统，该系统采用了一种应用于城市场景中的基于无连接的路由算法，并在Mac 层采用一种功率可调的方案改善网络通信质量。该文结合GPS/INS(全球定位与惯性导航)组合定位技术、地图匹配技术和多媒体技术等，实现车辆间的有效定位、无线通信和多媒体服务。该系统可应用于城市的各类交通系统中，给城市交通带来诸多便利，同时，对其他环境下的自组织网络应用也有一定的参考价值。关键词：ad hoc；CLA-S；GPS/INS；功率可调；车载系统Abstract：A new embedded vehicle system based on Ad Hoc is proposed in this paper. Compared with the traditional vehicle system，this system adopts a routing algorithm based on connectionless approach which is properly applied in city environments, and the quality of communication has been improved through a adjustable power method at the Mac layer. This paper discusses the implementation of effective positioning, wireless communication and the multimedia service between the vehicles, etc, integrated with the technology of GPS/INS positioning, map matching and embedded media processing. This system can be implied invarious types of traffic systems, bringing convenience to the city traffic. In the meantime, it can also serve as a useful reference to the applications of ad hoc networks in other environments.Key words：ad hoc; CLA-S; GPS/INS; power adjustable; vehicle system