基於軟體定義無線電之無線通訊系統設計

Abstract

無線通訊實體層的設計大部分是透過理論的推導和模擬來做驗證。然而，數 學模型仍然無法將現實生活中許多因素列入考慮，導致理論的分析不足以描述現 實世界的環境。過去的學者透過數位訊號處理器（DSP）或現場可程式邏輯閘陣列 （FPGA）的硬體來實現無線通訊實體設計，儘管如此，因為硬體語言的入門門檻 高，讓這些使用硬體語言程式的平台難以被實做出來。如今，因為軟體定義無線 電（SDR）的便利性及可重新配置性，讓它廣泛的被接受及使用。在本篇論文中， 我們利用軟體定義無線電（SDR）和通用軟體無線電周邊設施（USRP）的平台來設 計無線通訊系統。第一套系統是位元交錯調變碼系統，我們以封包錯誤率為該系 統效能評斷的依據。第二套系統是多天線系統，該系統裡實現了多天線正交多頻 分工系統的同步與通道估測。第三套系統是合作式通訊系統。第四套系統是無線 通訊實體層安全機制設計。最後，條列了對於使用軟體定義無線電實做系統的優 點與困難。

Most of the physical layer designs are verified through the derivation and simu- lation. However, there are several factors that mathematical model cannot take into considerations. The theoretical analysis is not enough to describe the real- world situation. Researchers used to implement the physical designs by Digital Signal Processor (DSP) or Field Programmable Gate Array (FPGA). Though, the hardware programming makes the testbed difficult to implement. The Software De- fined Radio (SDR) becomes prevalent for its convenience and reconfigurability. In this thesis, we design the wireless communication system utilizing the platform of GNU Radio and Universal Software Radio Peripheral (USRP). First, we construct a Bit-Interleaved Coded Modulation (BICM) system. The performance in terms of packet error rate is also evaluated in our implementation. Next, we extend the SISO OFDM into MIMO OFDM system. The designs of MIMO OFDM synchronization and channel estimation are conducted in this system. Furthermore, a cooperative communication system is verified in the real world transmission as well. A modified Physical Network Coding (PNC) scenario is designed and demonstrated its feasibil- ity. Finally, we list the advantages and difficulties when implementing these systems using GNU Radio and USRP.