Summary: | 碩士 === 國立清華大學 === 通訊工程研究所 === 101 === 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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