基于OMAP和ZigBee的车载无线对讲系统设计

On-Vehicle Wireless Walky-Talky System Based on OMAP and ZigBee

以车载多媒体系统为研发背景,在OMAP5912平台上结合支持ZigBee无线网络技术的模块,设计了无线对讲系统,实现了语音的无线传输功能。为了满足ZigBee技术低传输速率的特点,通过OMAP的DSP处理器,采用ITU-T制定的G.729a标准对语音进行编解码,在DSP上进一步对其进行优化,大大减少了处理每帧语音数据所需的时钟周期数。经测试,系统运行稳定,平均通话延时约1.9 s,符合对讲机性能要求。

For the research of vehicle electronic multi-media video and audio system,a wireless walky-talky system is designed by combining the OMAP5912 platform with the module which supports ZigBee（a wireless network technology）,and the wireless transmission of speech is implemented.To satisfy the low transmission rate of ZigBee,G.729a codec algorithm,which is developed by ITU-T,is adopted and running on the DSP processor of OMAP.The codec program is optimized on the DSP processor,and the needed processing clock cycles of speech data each frame are greatly reduced.Testing results show that this system can work stably with average time delay about 1.9 seconds,which fits the performance requirements of common Walky-Talky system.