The Research And Implementation Of The Physical Layer Ieee802.11B On Software-Defined Radio Platform

IEEE802.11b is a standard which specifies the physical layer (PHY) and medium access control (MAC) layer for wireless local area network (WLAN). This standard fundamentally changes the design and present application situation of the wireless local area network (WLAN) and fiilly achieves the requirements of hoping uninterrupted mobile office within a certain range while.creating space where the position is free from the constraints. The implementation of the physical layer IEEE802.lib on software-defined radio platform built by GNU Radio and USRP, supports for the study of signal processing algorithm without RF hardware. Software-defined radio makes IEEE802.11b signal processing modular, so that we can build a real-time and high capacity wireless communication system easily.In this paper, the key technologies of IEEE802.11b physical layer are introduced in detail and we design a complete solution of wireless communication system, including network structure, software and hardware architecture. According to the solution, the wireless communication system is implemented using the software-defined radio platform composed of GNU Radio and USRP2. The system consists of wireless signal transmitter and receiver modules, generator of frame, signal modulation and demodulation, clock recovery, cyclic redundancy check and so on, which helps better agreements of analyzing and supports for intelligent switch research of achieving a variety of different communication systems.This system has features as follows. First, work at2.4GHz. Second, make signal processing modular. Third, complete the various operations of signal through programming. Fourth, detect signal frequency spectrum dynamically.Finally, after testing the functions of the wireless communication system, we verify that the system successfully realized the sending and receiving of physical layer data.