Broadband Wireless Communication Networks, Automatic Repeat Request Mechanism

With increasing development of wireless communication, the demand on the variety and the quality of network operation becomes higher and higher. In order to insure the reliability of network transmission, error control technology arises. Among of these technologies, automatic repeat request (ARQ) has been wildely used because of its higher performance. In the rapid developmental wireless mobile communication system, the greatly improved transmission speed will make ARQ become one of the most pivotal technologies of Data Link Layer.From the view of development of ARQ technology, current ARQ technologies had resolved the problems of data transmission in wire network, but wireless network has high transmission delay and high bit error ratio. How to apply ARQ technologies better in wireless communication becomes an import problem to be solved. This paper will make efforts to research ARQ mechanism of boardband wireless communication and implement ARQ mechanism in the boardband wireless access technology IEEE802.16 to improve the reliability of 16e system.Above all, this paper introduces correlative knowledge of IEEE802.16 standard, and analyzes ARQ schemes basically, including its principle and category, and specially introduces the ARQ mechanism in IEEE802.16 protocol. Then aiming at the mobility supported edition IEEE802.16e, a detailed analysis is made to the ARQ mechanism in IEEE802.16e protocol. On the basis of this analysis, ARQ subsystem has been devided into Base Station ARQ subsystem and Mobile Station ARQ subsystem and both of them have been detailedly designed. According to the design, ARQ subsystem has been implemented roundly. After this, detailed testing of this ARQ subsystem has been taken in Linux kernel 2.6 environment and picochip-HDP. Through the analysis of testing result, conclusion could be made that this ARQ subsystem almost can realize all functions that required in IEEE802.16e protocol and basically comply with the IEEE802.16e Base Station and Mobile Station software system certification standards proposed by WiMAX Forum.