無線通訊系統，它與其它通訊系統最大的差異就在於它的通道(Channel)是無線的，也正因為如此，整個無線通訊系統的演算法都必需針對通道的特性來設計，才能夠達到最佳的效果。
例如無線通道中會有多路徑(Multi-Path)傳輸、延遲(Delay)、到達方向(Direction Of Arrival)、瑞雷衰減(Rayleigh Fading)等現象，這些現象會影響到整個演算法的可行性與正確性。所以預估通道的參數對於無線通訊系統而言是一件重要的事.

另外適應性(Adaptive)的訊號處理方法，由於能夠自動調整系統參數，常被用來預估通道參數並將接收到的訊號等化(Equalize)。其中Least-Mean-Squared(LMS)演算法為一穩定而易於實作的適應性演算法。

因此我設計了一個特殊應用積體電路(ASIC)，包含了無線通道擬真器(Wireless Channel Emulator)來模擬無線通道的特性，和一個適應性LMS等化器(Adaptive LMS Equalizer)來追蹤通道的參數。以便能將無線通道的特性與等化器的表現做一整合與分析。

這顆IC使用TSMC的.35製程,並且使用Avant的Cell-Library,是一顆數位的IC.工作頻率約二十Mhz左右.使用32pin DIP包裝.

The difference between wireless comm. and other comm. is that the channel of wireless comm. is wireless. From this, all the comm. systems should be designed according to channel specifics to improve performance. Otherwise, adaptive signal process methods are frequently used to estimate channel parameters. So I designed a specific integrated circuit (ASIC) which includes a channel emulator and an adaptive LMS equalizer.

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