在本論文中, 提出了一個4x4 的多輸入輸出正交分頻多工之內收發器之系統架構, 這內收發器乃是根據IEEE 802.16e OFDMA 的下行收發器之標準下去制定的。在通道的不理想效應方面, 加入了系統標準所規定的正負2ppm 之載波頻率偏移及取樣頻率偏移, 另外使用了3GPP 所制定的ITU-VA 及ITU-PB 之通道模型, 這裡為了滿足所使用之多輸入輸出訊號偵測器的假設, 我們設定所有傳送訊號之通道彼此間為獨立, 最後, 加入了督普勒效應, 以模擬此收發機在行動通訊環境時的接收狀態。

在本論文所提出之接收機中, 我們使用了延遲-相關之演算法架構去做封包之偵測, 再來使用了一匹配濾波器去做了訊號之精準時序的同步, 在時域軸的最後, 我們繼續使用了之前延遲-相關演算法之值來解出載波頻率偏移之值並補償之。而在訊號經過FFT 轉入頻域軸後, 我們先解回了之前回載波頻率偏移造成的子載波偏移, 接著即開始通道的估測, 這裡我們試了多樣內外插方式, 最後選擇出個可同時滿足ITU-VA 及ITU-PB 這兩種不同型態之通道的通道估測方式。最後訊號被送入多輸入輸出訊號偵測器並解回之。本系統在模擬的結果, 証實在行動速率100 km/hr 之行動環境下, QPSK 之調變方式仍可到達10□3 之位元錯誤率。

在完成了系統之後, 我們將這套系統套用在一高速模擬平台之上, 將其傳送端放入FPGA之中, 而接收端則保持軟體狀態以保持演算法開發之彈性, 藉由收發機軟硬體之間的共同模擬, 可望一來加速模擬速度, 二來保持演算法開發替換之彈性及便利性。藉由網頁的控制模擬也使得系統的使用者介面更加的友善更加的人性化, 這些因素都可望增進未來接收機端演算法開發之速度及便利性。

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