用於混合式陣列天線之訊號抵達/離開角度盲蔽估計

Abstract

數位或類比陣列天線的波束形成技術已經被應用於無線通訊系統。為了波束形成，接收端必須要知道訊號抵達的角度(Angle-of-arrival)同時傳送端也需要知道訊號離開時的角度(Angle-of-departure)。基於子空間的盲蔽估計演算法，例如MUSIC以及ESPRIT是廣為人知的訊號抵達角度估計的方法。近年來，混合式天線架構被學者提出來做為在天線陣列效能與成本之間的權衡。不幸的是MUSIC/ESPRIT無法在混合式天線中應用。在這篇論文裏，我們首先提出一種新的混合式天線盲蔽訊號抵達角度估計方法，接著我們更進一步將這一種方法延伸至訊號離開角度的估計。模擬結果顯示我們所提出的方法在使用混合式天線之OFDM系統上可以有令人滿意的效果。

Beamforming with digital or analog antenna array has been used in wireless systems. To conduct beamforming, the receiver has to know the angle of arrival (AoA) while the transmitter the angle of departure (AoD). Subspace-based blind method, such as MUSIC and ESPRIT, are well known for AoA estimation. Recently, hybrid array has been proposed as a compromise between performance and cost of antenna array. Unfortunately, MUSIC/ESPRIT cannot be used in hybrid arrays. In this thesis, we first propose a new blind AoA estimation method for systems with hybrid arrays. Then, we extend the method to conduct AoD estimation. Simulations show that the proposed methods perform satisfactorily for hybrid-array aided OFDM systems.