Synchronization Algorithm For Ofdm Based On Ieee802.11a Protocol

With the rapid increase of Internet, Broadband Wireless Access (BWA) technology has become a hot spot of the market because of its many advantages. And the WLAN is generally considered as the 'last mile' in the connection of computers and wired networks. In 1997, the first WLAN standards has approved, WLAN started to develop swiftly and violently. Latterly, the coming of IEEE802.11b and IEEE802.11a standards, the WLAN technology has been developed fast. And the Orthogonal Frequency Division Multiplexing (OFDM) is given more and more attention in wireless area, because OFDM lessens the severe effects of frequency selective fading and improves the spectrum efficiency, and this technology has been indicated to become a key technology in the fourth moving communication.In this paper, we emphasis on investigating a difficult view of OFDM, that is synchronization problems, who include frame synchronization, timing synchronization and carrier synchronization, at last we will simulate the whole system. This paper is organized as follows:Section 1 introduces the development general situation of the broadband wireless access technology and WLAN, then anatomies the channel characteristic of the WLAN, finally points out the mostly working of this paper.Section 2 emphasis on two points, one is IEEE802.11a standards, this is the transmission of the whole system, the other is the principle of OFDM technology and its excellent and shortcoming.Section 3 is the center of this paper, in this section researches the kinds of synchronization technologies. Firstly it studies the delay and frequency offset influencing the systems, then compares the actual synchronization technologies, indicates its shortcoming and improves it.Section 4 at the basis of the front sections, organizes the fine-capability and the low-complex synchronization technologies, simulates the whole systems in kinds of situations, and gives some conclusions.