Research On Multi-Channel Communication Techniques For Cooperative Mobile Streaming

The performance of mobile network has gained great improvement with the continuous development of wireless network technology.4G cellular networks and high performance Wi-Fi networks have been gradually popularized in people’s daily life. At the same time, due to the highly improved performance of mobile devices, mobile Internet has become one of the most important services in modern society.As one of the most important applications of the traditional Internet, streaming media service has been playing an important role in the Internet society. Furthermore, with the advent of the mobile Internet era, which shows a tendency of personalization and entertainment, the status of streaming media services enhanced further. The industry also makes more efforts on expanding it.However, unlike the traditional Internet, mobile Internet requires some access points to provide its service, like cellular base station or Wi-Fi AP. Due to its bandwidth bottleneck, the cellular suffers a great degradation under high user density. Meanwhile, Wi-Fi AP usually need some fixed infrastructures, which may cause some troubles in outdoor environment. Therefore, the D2D service mode has grabbed the interest of the industry and is considered as the key to the improvement of the performance and service quality of mobile Internet. Based on the facts above, our team designed and implemented a "Smartphone oriented collaborative streaming media service system" (MANET). This system uses smartphone as a platform, and it shares streaming media data between smartphones through the Ad Hoc network. By using this system, users can lower their cellular data cost and improve the service quality when using streaming media services.In many high user density application scenarios, the performance of Wi-Fi Ad Hoc network still has some bottleneck. Based on this problem, this thesis makes a research on the performance optimization of Ad Hoc network. The main contents are as follows:1)Bluetooth collaboration based multi-channel communication system. In MANET system, users cannot get sufficient bandwidth when the number of user is high. In order to solve this problem, this thesis designed a multi-channel communication system based on Bluetooth collaboration. By using multiple channels simultaneously, the performance of Ad Hoc network can be significantly enhanced. On the other hand, unlike traditional multi-channel works, the system does not require the modification of existing hardware and protocols. According to the transmission characteristics of streaming media applications, the system has been optimized to achieve a substantial increase in Ad Hoc network performance, which provides higher network throughput capacity and higher quality of streaming media services.2)Multi-channel communication optimization based on time domain characteristics. Differs from that of wired networks, the throughput capacity of wireless network is unstable. Because of its vulnerability to external interferences, the quality of each Wi-Fi channel fluctuates. While in the multi-channel communication system, reasonable allocations of channel resources can improve the performance. According to this theory, this thesis proposes a channel assignment strategy and algorithm based on the time domain characteristics. Through this algorithm, the performance of the multi-channel system can be boosted when the wireless network environment is unstable.