在科技不斷進步之下,傳統家庭數位化的發展是必然的趨勢,然而,數位化家庭的佈線與架設裝置都需要消耗大量成本,不過在每個家庭中都有完善的電源設施,所以電力線可以說是一般家庭內之最佳傳輸媒介,用其進行資料傳輸、網際網路及遠端監控等工作。本文主要是利用FPGA晶片來實現正交分頻多工(OFDM)之調變以進行信號在電力線傳輸,首先將輸入資料進行前向錯誤糾正技術(FEC)之編碼,將其結果進行正交分頻多工之調變後,以電力線為傳輸媒介來做資料傳輸,再將電力線上擷取到的資料以正交分頻多工做解調,最後再做錯誤更正碼之解碼以還原原始資料。 本文所使用的FPGA晶片為Altera公司所開發之Stratix系列實驗板,其中IFFT/FFT轉換以及FIR濾波器是利用Altera公司所設計之IFFT/FFT 、FFT MegaCore Function來實現。本文利用耦合電路將訊號耦合至電力線通道,並分別為改變電力線長短與在不同位置上並聯負載兩種方式作為測試,錯誤率並無明顯上升,另一探討訊號雜訊比(SNR)作錯誤率之統計,結果顯示藉由改變編碼方式,能使資料錯誤率降低至最小。
Because of the progress of science and technology, the digital improvement of traditional household is an inevitable trend. However, the wiring and device of the digital house require high cost. There is almost a perfect power facility in every household. Therefore, power line is the best transmission media applying to data communication, internet and monitoring in the remote side. This thesis mainly developed the Orthogonal Frequency Division Multiplexing Modulation (OFDM) by using Field Programmable Gate Array (FPGA) in order to accomplish power line communication. Firstly, the input data need to be encoded with Forward Error Correction (FEC) and then the results are sent to the OFDM modulation. Then the power line is used to deal with data communication which is prepared for decoding with OFDM. Finally, it has to do the decode of error code for the sake of returning original data. In this thesis, an FPGA, which is an experiment board developed by Altera company, is used. The IFFT/FFT and FIR are conducted by MegaCore Functions designed by Altera company. We send the signal onto power line channel by coupling circuit and find that the error rate doesn’t increase when testing by varying the lengths of the power line and the parallel load in different positions. The error rate also studied through different signal noise rates (SNR). It can be found that the corresponding error rate can be reduced by changing the modulations.