703无线局域网IEEE 802.11

802.11--CSMA/CA机制简述 802.11-CSMA/CA简述 1. 概述   在最初的802.11中MAC层中,共有两种基本的工作模式:   1. Distributed Coordination Function,简称DCF;   2. Point Coordination Function,简称PCF;   DCF采用的是竞争的方式接入信道,PCF则采用统一分配的方式接入信道,在多ap的环境下,需要更加复杂高效的额外方式,来实现重叠频信道接入控制;   DCF因为有良好的分布式特性,从而DCF被广泛使用,PCF则比较少使用,最先的 阅读详情

目录

IEEE802.11体系结构

IEEE 802.11的MAC协议

IEEE 802.11帧


 

IEEE802.11体系结构

 

1.基站AP

2.基本服务集BSS

AP发现:主动扫描探测帧、被动扫描信标帧

 

 

IEEE 802.11的MAC协议

 

CSMA/CA——带碰撞避免的CSMA

CSMA/CA通过RTS赫CTS帧的交换,可以实现信道的预约占用,避免数据帧传输过程中的冲突

 

 

IEEE 802.11帧

 

1.IEEE802.11的帧类型:

控制帧、数据帧、管理帧

 

瑞芯微 RK356x 基于Android11移植usb接口rtl8723du wifi和蓝牙一体化 Realtek RTL8723DU是一个高度集成的单片机802.11b/g/n 1T1R WLAN,和一个集成的蓝牙2.1/4.2单片机,USB 2.0多功能。它将一个WLAN MAC、一个支持1T1R的WLAN基带、BT协议栈(LM、LL和LE)、BT基带、调制解调器和WLAN/BT RF结合在单个芯片中。RTL8723DU为一个高性能集成的无线局域网和蓝牙控制器提供了一个完整的解决方案。RTL8723DU WLAN基带实现了1发射和1接收路径的正交频分多路复用(OFDM),并与802.11n规范兼容。 阅读详情

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