无线局域网新型MAC层接入机制仿真研究
发布时间：2018-11-28 12:38
【摘要】：近年来,随着无线通信技术的迅猛发展,WLAN因其拥有高的数据吞吐量、高灵活性、低成本、易于扩展等特点,已经被广泛应用在人们的工作和日常生活中。同时,相比于传统的有线网络,无线局域网的性能和服务质量仍有着很大的差距,因而无线局域网成为近年来研究的热门课题。媒体访问控制(MAC)层是无线局域网的重要组成部分,MAC层协议性能对无线局域网的性能起着至关重要的作用。为了使无线局域网更好地满足现代通信网络的要求,MAC层接入机制的研究和优化具有相当重要的研究意义。因此,本文主要对无线局域网WLAN中MAC层接入机制进行了研究。本文在简要分析了课题的研究背景及意义、国内外研究现状以及相关的基本概念的基础上,详细介绍了 MAC层协议内容和工作原理。DCF接入机制是MAC层协议中基本的接入控制方式,因此本文针对分布式协调控制(DCF)接入机制进行了深入研究,并对DCF算法的改进机制进行了研究。主要包含以下几个方面:首先,通过对DCF接入机制的工作原理的研究,对DCF机制进行了性能仿真,包括系统的吞吐量、碰撞概率等,仿真结果表明最小窗口、传输速率、站点个数、数据帧长对系统的性能都有一定的影响。其次,研究了一种对DCF机制中的退避机制的改进方案,对该机制进行了仿真,并将改进机制的性能参数与传统机制的性能参数进行了对比分析,仿真结果证明该改进机制可以提高系统性能。接着,针对带碰撞避免的载波侦听多址接入(CSMA/CA)机制提出了两种改进方案:吞吐量最优空闲信道检测(CCA)门限设置的方案和基于RSSI的CCA门限动态调整的方案,通过对两种机制的性能进行仿真分析,验证了这两种改进方案都可以在一定程度上提高系统的性能。
[Abstract]:In recent years, with the rapid development of wireless communication technology, WLAN has been widely used in people's work and daily life because of its characteristics of high data throughput, high flexibility, low cost and easy to expand. At the same time, compared with the traditional wired networks, the performance and quality of service of WLAN is still a big gap, so WLAN has become a hot research topic in recent years. Media access control (MAC) layer is an important part of WLAN. The performance of MAC layer protocol plays an important role in WLAN performance. In order to better meet the requirements of modern communication networks, the research and optimization of MAC layer access mechanism is of great significance. Therefore, this paper mainly studies the access mechanism of MAC layer in WLAN. Based on a brief analysis of the background and significance of the research, the current research situation at home and abroad and the related basic concepts, The content and working principle of MAC layer protocol are introduced in detail. DCF access mechanism is the basic access control mode in MAC layer protocol. Therefore, the distributed coordinated control (DCF) access mechanism is deeply studied in this paper. The improved mechanism of DCF algorithm is also studied. The main contents are as follows: firstly, through the study of the working principle of DCF access mechanism, the performance simulation of DCF mechanism is carried out, including system throughput, collision probability and so on. The simulation results show that the minimum window, transmission rate, etc. The number of sites and data frame length have a certain impact on the performance of the system. Secondly, an improved scheme of Backoff mechanism in DCF mechanism is studied, and the performance parameters of the improved mechanism are compared with those of the traditional mechanism, and the performance parameters of the improved mechanism are compared with those of the traditional mechanism. Simulation results show that the improved mechanism can improve the system performance. Then, two improved schemes for carrier detection multiple access (CSMA/CA) with collision avoidance are proposed: the optimal throughput free channel detection (CCA) threshold setting scheme and the CCA threshold dynamic adjustment scheme based on RSSI. Through the simulation analysis of the two mechanisms, it is proved that the two improved schemes can improve the performance of the system to a certain extent.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN925.93
本文编号：2362844
[Abstract]:In recent years, with the rapid development of wireless communication technology, WLAN has been widely used in people's work and daily life because of its characteristics of high data throughput, high flexibility, low cost and easy to expand. At the same time, compared with the traditional wired networks, the performance and quality of service of WLAN is still a big gap, so WLAN has become a hot research topic in recent years. Media access control (MAC) layer is an important part of WLAN. The performance of MAC layer protocol plays an important role in WLAN performance. In order to better meet the requirements of modern communication networks, the research and optimization of MAC layer access mechanism is of great significance. Therefore, this paper mainly studies the access mechanism of MAC layer in WLAN. Based on a brief analysis of the background and significance of the research, the current research situation at home and abroad and the related basic concepts, The content and working principle of MAC layer protocol are introduced in detail. DCF access mechanism is the basic access control mode in MAC layer protocol. Therefore, the distributed coordinated control (DCF) access mechanism is deeply studied in this paper. The improved mechanism of DCF algorithm is also studied. The main contents are as follows: firstly, through the study of the working principle of DCF access mechanism, the performance simulation of DCF mechanism is carried out, including system throughput, collision probability and so on. The simulation results show that the minimum window, transmission rate, etc. The number of sites and data frame length have a certain impact on the performance of the system. Secondly, an improved scheme of Backoff mechanism in DCF mechanism is studied, and the performance parameters of the improved mechanism are compared with those of the traditional mechanism, and the performance parameters of the improved mechanism are compared with those of the traditional mechanism. Simulation results show that the improved mechanism can improve the system performance. Then, two improved schemes for carrier detection multiple access (CSMA/CA) with collision avoidance are proposed: the optimal throughput free channel detection (CCA) threshold setting scheme and the CCA threshold dynamic adjustment scheme based on RSSI. Through the simulation analysis of the two mechanisms, it is proved that the two improved schemes can improve the performance of the system to a certain extent.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN925.93
【引证文献】
相关期刊论文 前1条
1 卢玫欣;苏胜君;施伟斌;乐燕芬;李瑞祥;;Z-MAC协议改进算法[J];软件导刊;2017年12期
，本文编号：2362844
本文链接：https://www.wllwen.com/kejilunwen/xinxigongchenglunwen/2362844.html
