合作式通訊下以多輸入多輸出和正交分頻多工之接收端對抗多重頻率偏移

Abstract

在合作式通訊下，同步是一個很重要的議題，不像傳統的多輸入多輸出(MIMO)系統，合作式的天線是分屬於不同的中繼端，因此，對目的端而言，很難同時補償多重頻率偏移(MCFOs)，另外，傳統的空頻區塊碼在這邊可能不是很適用，在這篇論文裡，我們考慮從中繼端到目的端的通道是頻率選擇性衰減通道，提出的方法是結合兩個已分別做完同步的訊號來消除載波間干擾(ICI)，疊代式干擾消除被進一步用來獲得良好的位元錯誤率以及對於多重頻率偏移有更好的容忍度。

Synchronization is an important issue in cooperative communications. Unlike in conventional MIMO systems, the cooperative antennas belong to different relay nodes. Therefore, it is hard for the destination node to compensate multiple carrier frequency offsets (MCFOs) simultaneously and the conventional space-frequency decoding may not be suited here. In this paper, we consider the cooperative transmission with MCFOs when the channels from relay nodes to the destination node are frequency selective fading. The proposed strategy which takes cues from literature [9] combines two sets of separately synchronized signal to mitigate inter-carrier interference (ICI). Iterative interference cancellation is deployed to further improve performance and tolerance of MCFOs.