Research Of DMR Implementation Technology Of L138 Embedded System

Over the past decade, the development of mobile communication technology was quickly. In the field of professional radio, communication technology has also experienced the updates from analog to digital. Nowadays, there have been many popular professional protocols, including TETRA, DPMR, PDT, Go Ta etc. Launched in 2005, DMR protocol has the advantage of low cost, easy implementation, compatible with analog interphone,-etc. Meanwhile, with more and more powerful hardware performance, as well as the increasing complexity of the system implementation, the demand for the use of operating system to manage interphone is also getting stronger.This article is aiming at implementing the embedded Linux operating system and SYS/BIOS system into the HD866 experimental board, writing communication program and control software, and finally, realizing the communication functionality according to the DMR protocol on the experimental board.This paper introduces the hierarchical structure and frame structure of the DMR protocol, and then it explores the embedded Linux operating system kernel and the various modules of Syslink.Since the Linux operating system and SYS/BIOS system are running on the OMAP-L138 simultaneously, a deep research of the real-time performance of the embedded Linux operating system and SYS/BIOS system is done. The result shows that the SYS/BIOS system can afford the demand of DMR protocol. Thus this paper assigns different programs to Linux operating system and SYS/BIOS system, according to the real-time performance.The article presents the transplantation of the embedded Linux operating system, the configuration of SYS/BIOS system and the preparation of related control software. The transplantation of the embedded Linux operating system is through the u-boot, the Linux kernel, file system and other steps. After the transplanting, the article describes the configuration of SYS/BIOS system in details. The communication program between L138 ARM core and L138 DSP core has been written. It can be divided into three parts, the dual-core communication program of Syslink, the design of shared memory program, the message queue program. On the basis of the message queue program, the article finishes the signaling procedure control program and overall control program.At last, the article presents the realization of the experimental board based on OMAP-L138. The main chips and circuits' design of various parts of the hardware, including minimized microprocessor system, voice system, radio frequency interface and network system were studied. Results for debugging hardware circuits have been described.The article gives the hardware and software design of each part. Various experiments have been designed for different parts. The results are also analyzed.