The TDMA MAC Protocol for Wireless Mobile Backhaul Network

• Main Authors: Su, Yi-Xing, 蘇益興
• Other Authors: Hsu, Terng-Yin
• Format: Others
• Language: en_US
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/hn67ma

碩士 === 國立交通大學 === 資訊科學與工程研究所 === 103 === For a mobile network, the most important issue is coverage. Using wireless method to extend the base station is better than the traditional wired method. It is quicker and easier to achieve the high coverages, and saving costs. Especially extend base stations in the suburbs by using the wired method, it will be more difficult and more expensive. So using the wireless technology can show its advantages significantly. However, wireless method faced many challenges. The most important problem is that all the base stations are using the same medium in the local area, it maybe cause the collision. So we need a mobile switch center to control and coordinate these base stations, to efficiently use the share medium and avoid collision in the entire wireless mobile backhaul network. In this paper, we set up a network which farthest distance is 2 miles, can connect up to eight base stations, and has a QoS control and high throughput. So we focused on such a wireless mobile bakchaul network, proposed a TDMA MAC protocol, on the MAC layer to control and coordinate the transmission of these base stations. The transmission unit in the MAC protocol is superframe. Each superframe duration is 65 ms, including the beacon period, UL groups and DL groups. Every four superframes provide a joinable period to allow one base station to join the network. We also simulated the MAC protocol to learn more information. Finally, we verified the entire transmission behavior of the MAC protocol via two FPGA boards. The data resource was from host to MAC protocol. We used the software method to program the MAC protocol on a FPGA, and the another FPGA was used to simulate the channel by hardware. When the the data was transmitted to the channel by MAC protocol, it had the probability to occur the propagation error. In the data transmission, the transmission protocol was I2C protocol between the two FPGA boards, and we used Ethernet to transmit data between the host and the FPGA which was running the MAC protocol. During the system platform operating, the system will print out the status and information for each frame transmission. According to these messages, we can verify the correctness of each function which includes the join function, time sync function, ACK and retransmittion function, error detection, the disconnection detection, and the QoS verification. To ensure the correctness and stability of this platform.