智慧型天線於寬頻分碼多重進接存取系統之應用

The Applications of Smart Antenna in W-CDMA System

賴智揚(Chih-Yang Lai)

指導教授 ： 鄭獻勳 ； 繆紹鋼

中原大學/工學院/電子工程研究所/碩士(2002年)

https://doi.org/10.6840/cycu200200159

摘要

在無線通訊系統裏，智慧型天線系統是在基地台安置一組陣列天線來取得發射信號的空間特徵(spatial signature)或信號的到達方向(Directions-Of-Arrival, DOAs)，再經由波束合成(beamforming)技術正確的取出我們所要的信號。它利用空間分隔多重進接存取(Space Division Multiple Access, SDMA)的概念，應用空間分集之特性來區分不同方位的使用者，達到減少同頻干擾的效應和多重路徑傳輸所造成的信號衰落現象，以增加頻道容量，提高通訊品質。為了制定第三代無線通訊系統IMT-2000的規格，在國際通訊聯盟(ITU)所徵求的無線通訊傳輸技術規格建議書(Radio Transmission Technology Proposals)，也已將智慧型天線系統的功能列入其IMT-2000的規格建議書之中，因此本論文的目的是在探討使用波束合成技術的智慧型天線應用在由3GPP所制定之W-CDMA系統的效能表現。
首先，本論文將介紹智慧型天線系統之基本概念並說明本論文中所採用之系統架構，其次再對3GPP所制定之W-CDMA系統作一簡介；最後，本論文將使用MATLAB模擬軟體來發展收發機子系統之軟體模擬模組，以模組化之方式建構W-CDMA之系統架構，再整合智慧型天線之波束合成演算法則以驗證智慧型天線應用於W-CDMA系統上之功能與效益。由模擬結果，使用波束合成的W-CDMA系統可使在特定訊雜比時的位元錯誤率降低，並於特定的訊號干擾比下容納較多的使用者，甚至於估測到的入射角度與實際角度間產生偏差時亦成立。因此，W-CDMA系統使用智慧型天線可得到較高的通訊品質及較大的系統容量。

關鍵字

智慧型天線 ； 寬頻多重進接存取系統 ； 波束合成演算法則

並列摘要

In wireless communications, a smart antenna system utilizes an array antenna at the base station to acquire the spatial signatures or directions of arrival (DOAs) from transmitted signals and extract the desired signals by adopting the beamforming technology. By applying the general ideas of space division multiple access (SDMA) schemes, smart antennas can suppress the co-channel interference and reduce multipath fading to obtain diversity gain, increase the channel capacity, and improve communication quality. Moreover, The Radio Transmission Technology (RTT) Proposals submitted to ITU for the 3rd generation wireless communications, IMT-2000, is adopting smart antenna into IMT-2000 recommendation. The purpose of this thesis is to evaluate the performance of smart antenna applied to the W-CDMA system standardized by 3GPP.
We first introduce the basic concept of smart antenna systems and illustrate our system architecture. Then, the W-CDMA system proposed by 3GPP will be described. Finally, we construct the W-CDMA system in modules and integrate with the beamforming algorithms to study the performance of applying smart antenna technology to W-CDMA systems. In the thesis, the function blocks of the transceiver subsystems will be developed and simulated in MATLAB. From simulation results, a W-CDMA system with beamforming could decrease the bit error rate at the specific SNR and accommodate a greater number of users at the specific SIR even though a certain angle difference existed between the actual and estimated DOAs. Therefore, the W-CDMA systems use the smart antenna technology can obtain higher transmission quality and larger system capacity.

並列關鍵字

Beamforming Algorithm ； Smart Antenna ； W-CDMA System

參考文獻

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