嵌入式设备通讯子系统的功耗优化研究

发布时间：2018-06-30 20:22

本文选题：智能手机 + 低功耗　；参考：《西北大学》2014年硕士论文

【摘要】：当今,嵌入式技术飞速发展,嵌入式设备日益普及,以智能手机、pad为代表的智能嵌入式移动设备逐渐成为大众化计算平台。为了提升设备性能,丰富用户使用体验,嵌入式移动设备的硬件和软件都在不断的升级和更新,但单纯的性能提升必然会降低设备的续航时间,而有限的电池容量并不能满足用户的需求。研究结果显示,嵌入式移动终端通讯子系统的能耗占整个系统能耗较大比例。随着3G网络的普及,人们使用手机网络进行通讯的频率越来越高,从而进一步加重了嵌入式移动终端的能耗负担。本文分别从网络传输协议和网络数据下载策略这两个角度来研究相应的功耗优化方案。完成的主要内容如下： 1：对国内外嵌入式系统功耗优化研究方案进行分类,总结。在相关技术研究中,首先,总结了现存于Android系统的能耗漏洞,重点研究了其中的No-sleep Bug。然后,阐述了本文的研究基础Lyapunov理论,动态系统及什么是稳定系统。 2：针对智能手机中标准TCP/IP协议的不足,分析其拥塞控制策略在网络通讯中的能耗问题。并深入研究了其它非对等式XCP协议、Reliable Blast UDP (RBUDP)和UDP-based Data Transport(UDT)协议的拥塞控制策略对能耗的影响。 3：针对智能手机中网络下载策略(立即响应下载)的不足,提出了基于Lyapunov优化框架的集中下载低功耗稳定链路选择算法(CLSA)。新策略的核心思想是本文提出的优化的消费者模型。而对于优化模型无法解决的无限等待问题,利用Lyapunov优化框架对网络等待队列进行分析,在网络状况不理想时,CLSA会保证下载请求队列稳定性的同时,延迟数据下载,这样避免了在低速环境中进行下载所产生的高能耗。随着下载队列的增长,即便在较差的网络环境中,CLSA也会对部分请求进行下载,这样避免了下载请求队列过长导致的不稳定性。 4：针对网络传输协议的实验,本文利用NS-2平台对标准TCP, UDT, RBUDP,XCP协议分别进行了仿真,分析仿真结果,本文得出在专享高速链路中,RBUDP能耗最低,在共享链路情况下XCP协议性能最优,能耗最低。 5：针对网络下载策略的实验,本文基于Android开源平台开发了一款音频下载播放软件,并将CLSA加入其中。实验将CLSA策略同另外两种通用下载策略(WiFiOnly, Minimum Delay)进行比较。结果表面,本文提出的CLSA下载策略能够很好的权衡了能耗和延迟的关系,能效比最高,性能最优。
[Abstract]:Nowadays, with the rapid development of embedded technology and the increasing popularity of embedded devices, smart embedded mobile devices, represented by smart phones, are gradually becoming popular computing platforms. In order to improve the performance of the device and enrich the user experience, the hardware and software of the embedded mobile device are constantly upgraded and updated. And limited battery capacity can not meet the needs of users. The results show that the energy consumption of the embedded mobile terminal communication subsystem accounts for a large proportion of the whole system energy consumption. With the popularity of 3G network, the frequency of mobile phone communication is becoming higher and higher, which further increases the energy consumption burden of embedded mobile terminal. In this paper, the corresponding power optimization schemes are studied from the network transmission protocol and the network data download strategy. The main contents are as follows: 1: the research programs of power optimization for embedded systems at home and abroad are classified and summarized. In the research of related technologies, firstly, the existing energy consumption vulnerabilities in Android system are summarized, and the No-sleep Bug. Secondly, the Lyapunov theory, dynamic system and what is a stable system are discussed. 2. Aiming at the shortage of standard TCP / IP protocol in smart phone, the energy consumption of congestion control strategy in network communication is analyzed. The influence of congestion control strategies of other non-peer-to-peer XCP protocols such as reliable blast UDP (RBUDP) and UDP-based data Transport (UDT) on energy consumption is studied. A low power stable link selection algorithm (CLSA) based on Lyapunov optimization framework is proposed. The core idea of the new strategy is the optimized consumer model proposed in this paper. For the infinite waiting problem which can not be solved by the optimization model, the Lyapunov optimization framework is used to analyze the waiting queue of the network. When the network condition is not ideal, CLSA will ensure the stability of the download request queue and delay the data download. This avoids the high energy consumption generated by downloading in low-speed environments. As download queues grow, even in poor network environments, CLSA downloads some requests, thus avoiding the instability caused by the long queue of download requests. In this paper, we use NS-2 platform to simulate the standard TCP, UDTand RBUDP XCP protocols, and analyze the simulation results. It is concluded in this paper that the energy consumption of RBUDP is the lowest in the exclusive high-speed link, and the performance of the XCP protocol is the best in the case of shared links. Energy consumption is the lowest. 5: aiming at the experiment of network download strategy, this paper develops an audio download and playback software based on Android open source platform, and adds it to it. The CLSA strategy is compared with the other two common download strategies (WiFiOnly, Minimum delay). The results show that the CLSA download strategy proposed in this paper can balance the relationship between energy consumption and delay, the energy efficiency ratio is the highest, and the performance is the best.
【学位授予单位】：西北大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TP368.1;TN929.53

【参考文献】