以FPGA為基礎之WiMAX上鏈接收機設計實現與測試

無線通訊系統在近幾年來的發展非常迅速，其傳輸速率(Data Rate)與品質的需求也不斷提昇，而正交分頻多工(Orthogonal Frequency Division Multiplexing, OFDM)的調變技術，由於對頻譜的使用效率較高，因此能提供較高的傳輸速率；另外此技術較能抵抗無線通道的多路徑衰減(Multipath Fading)，有助於提昇傳輸品質，因此非常適合應用在目前的都會區環境。在眾多應用於都會區無線網路的規格裡，WiMAX系統提供了高速、長程與高品質的傳輸，其中802.16d與802.16e分別是固定式與移動式的系統，本論文的研究主要是以固定式的系統為主，根據IEEE 802.16-2004 WirelessMAN-OFDM實體層(Physical Layer)規格，設計上鏈收發機系統之硬體電路，將其實現於FPGA上，並透過閉路(Close Loop)測試，實際將用戶發射端產生的類比訊號送給基地台接收端；另一方面為了實際驗證本系統，在個人電腦端設計了基本的MAC(Medium Access Control)層管理程式，以方便對實體層進行各種設定；最後利用PPC(Power PC)建立溝通介面，將FPGA與個人電腦銜接起來，完成一套可以自行收發資料的通訊系統。本論文之貢獻在於將WiMAX上鏈系統實際呈現在一個具有FPGA與PPC的發展版上，並提供基本的MAC層控制，讓使用者能在PC端控制並驗證此系統。而本系統上所有模組化的電路設計，也能方便使用者自行研發效能更好的模組來進行抽換，為之後的研究者提供了一個完整的硬體測試環境。

關鍵字

無線通訊； WiMAX ；實體層；正交多頻分工

並列摘要

Wireless communications is a rapidly growing industry nowadays. As the requirement of transmission rate and quality is higher and higher, more related researches are developed. The technique of OFDM is proposed with some benefits. The higher spectral efficiency provides higher transmission rate. Besides, OFDM can reduce the distortion due to multi-path fading to improve the transmission quality. These advantages make OFDM to be a suitable technique for typical metropolis environment. In several communication standards, WiMAX provides the higher data rate, the farther transmission distance, and the better communication quality. In this thesis, we implement a uplink WiMAX transceiver on a development board with FPGA and PPC based on the IEEE 802.16-2004 WirelessMAN-OFDM standard which is used for fixed transmission applications. The physical layer architecture is accomplished on the FPGA. On the other hand, the basic MAC is achieved with the PPC to provide the communication interface between PC and FPGA. This system can be verified by the close loop testing, that is, transmit analog signal generated by subscriber station transmitter to the base station receiver on the same board. Then we can send the transmission data from PC to this system, and get the decoded result back. The contribution of this thesis can be summarized as follows. We implemented the uplink WiMAX system on the development board with FPGA and PPC. Users can control and verify this system from PC conveniently. Besides, the modularly designed structure makes users do any modifications easily. This provides an integrated hardware platform for the further researchers.

並列關鍵字

WiMAX ； OFDM ； PHY ； 802.16d

參考文獻

[1] IEEE 802.16-2004, "IEEE Standard for Local and Metropolitan Area Networks Part 16: Air Interface for Fixed Broadband Wireless Access Systems," IEEE Std., 2004

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[4] Bo Ai, Zhi-xing Yang, Chang-yong Pan, Jian-hua Ge, Yong Wang, Zhen Lu, "On the Synchronization Techniques for Wireless OFDM Systems," IEEE Transactions on Broadcasting, vol.52, No. 2, pp.236-244, June 2006

[6] Jun Wu, Qun Zhou, Cheng, K.K.M., "The adaptive algorithm of symbol timing and carrier phase estimation in OFDM systems," Communications, 2001. ICC , 2001. IEEE International Conferrence on vol. 1, pp.156-160,11-14 June 2001

[7] C. Berrou, P. Adde, E. Angui, and S. Faudeil, "A low complexity soft-output Viterbi decoder architecture," in Proc. IEEE Int. Conf. Communications, pp. 737-740, 1993

國際替代計量

以FPGA為基礎之WiMAX上鏈接收機設計實現與測試

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