OFDM系統在60 GHz頻帶之非直視傳輸： 使用混合式陣列天線之DoA估計與定位

Abstract

IEEE 802.15.3c系統是一適合高速之上網或高畫質之影音傳輸的規格，但操作的頻段是在免執照的57 ~ 64 GHz 的頻段，由於此頻段通道對訊號有嚴重的路徑損失、反射損失及其他衰減的問題。為了解決路徑損失這些問題，混合平面陣列天線(hybrid planar antenna arrays)被提出用以波束形成的傳輸與接收。本論文在探討60GHz系統中LOS/NLOS之傳輸技術與多使用者環境的定位問題。首先，我們提出遞迴的波束搜尋法，可快速且精確地搜尋出最佳的波束對。同時，我們針對環境須由NLOS變動成LOS提出一偵測架構。最後，我們考量到多使用者環境中的定位問題。我們提出兩個方法分別為角度法及座標法來估計使用者之間的相對位置。在已知使用者間的相對位置情況下，波束形成可以進行用戶對及多個排程平行傳輸有效改善系統吞吐量。

IEEE 802.15.3c system offers data rates of multiple Gbit/s for applications such as high speed internet access or high quality video streaming and it is operated in unlicensed 57-64 GHz band. However, this band is suffering from high path loss, high penetration loss, and other problems. To alleviate the path loss problem, hybrid planar antenna arrays have been proposed for bemaformed transmission/receiving. In this thesis, we consider LOS/NLOS transmission technologies for 60GHz systems and the localization problem in the multiuser environment. First, we propose a recursive beam matching method, which can find the best transmit and receive beamforming pair. Then, we propose a sensing scheme that can detect the environment change from NLOS to LOS. Finally, we consider the localization problem in the beamformed multiuser environment. We propose two methods, the angle and coordinate method, such that the relative positions of users can be estimated. With the relative positions, beamforming can be conducted for user pairs and multiple parallel transmissions can be scheduled to enhance the system throughput.