(研究生论坛)IEEE802.11g无线局域网中基于FrFT角分多址的多流OFDM技术

为了提高数据传输速率，本文把分数阶傅立叶变换（FrFT）角度看作一种时频联合资源，通过设计最优分配准则提出IEEE802.11g无线局域网（WLAN）中基于FrFT角分多址（ADMA）的多流正交频分复用（OFDM）技术。发送端通过不同角度的逆分数阶傅立叶变换（IFrFT）对多个数据流进行调制，由于每个数据流中不同子信道上调制基函数的相互正交性，以及不同数据流之间相同子信道上调制基函数的近似正交性，接收端可以通过FrFT域相关检测很好地抑制各数据流间干扰。最后的仿真结果表明：相比传统IEEE802.11g中单流OFDM技术，系统传输速率可以得到显著提高。

The Multi-stream OFDM technology based on FrFT Angle Division Multiple Access in IEEE802.11g WLAN

In this paper, fractional Fourier transform (FrFT) angle was regarded as a kind of time-frequency combined resource, and a novel multi-stream orthogonal frequency division multiplexing (OFDM) technology based on FrFT angle division multiple access (ADMA) was proposed in IEEE802.11g wireless local area network (WLAN) by designing optimal allocation criteria for improving data transmission rate. At the transmitter, multiple streams were modulated by inverse FrFT with different angles, and at the receiver, due to the mutual orthogonality between base functions of identical stream at different sub-channels, and the nearly mutual orthogonality between base functions of different streams at same sub-channels, the inter-stream interference could be perfectly suppressed by correlative detection in FrFT domain. The final simulation results showed that the transmission rate could be improved greatly, comparing with conventional single-stream OFDM technique in IEEE802.11g.