近年來由於寬頻用戶的大幅增加以及網際網路多媒體服務需求的成長，如此高傳輸量的通訊系統成為了一項重要的議題。而光學正交分頻多工(Optical OFDM)傳輸之傳送接收器的實現就變得相當重要。在本論文中介紹了正交分頻多工的理論以及光學正交分頻多工中的直接偵測與同調偵測，並且提供了光學實驗架構包含了光學傳送接收器以及光纖通道，最後設計了一16 路平行化運算處理之基頻正交分頻多工接收器包含了IQ mixer、frame detection、remove CP、FFT 以及channel estimation，並將之實現在FPGA(SMIMS-V4VLX160)上並且在直接偵測光學正交分頻多工系統上做結合，其中AWG 之取樣速度為12GS/s，RTS 為2GS/s。此外所設計的基頻正交分頻多工接收器系統速度為7.791ns(128.353MHz)，可達到1.62Gb/s 的運算吞吐量。

In the recent years, the technology of communication devices is developed rapidly due to the growing demand for transmission system. Therefore, the high capacity of communication systems becomes an important issue. In order to provide large bandwidth for high quality services, realizing a transceiver for optical OFDM system becomes very important. This study presents the theoretical fundamentals of the OFDM technology and the direct detection and coherent detection in optical OFDM systems. This work also builds an experimental environment including the optical transmitter, fiber channel and the optical receiver. Finally, this thesis proposes a FPGA design and implementation of the baseband OFDM receiver including IQ mixer, frame detection, remove CP, FFT and channel estimation with 16 parallelism. The design of the baseband OFDM receiver was successfully implemented in an FPGA (SMIMS-VC4VLX160) and demonstrated in the direct detection optical OFDM system with the sampling rate of AWG equals to
12GS/s and RTS equals to 2GS/s, each sample contains 10bits. Besides, the system clock is 7.791ns (128.353MHz). Thus the throughput can achieve up to 1.65Gb/s.

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