結合抑制無線電頻率干擾之時域等化器設計

Abstract

無線電頻率訊號會降低以DMT為系統的數位用戶線路的傳送效能。無線電頻率訊號本質上是窄頻訊號，它可能會因為通過接收端矩形窗所產生的高旁波值而影響到無線電頻率附近的子通道。在這篇論文裡，我們提出同時考慮通道縮短和抑制無線電頻率干擾來設計時域等化器。設計方法是藉由將ISI，通道雜訊和無線電頻率訊號的影響最小化來達到目標。我們將會用模擬結果來說明提出的方法能夠大幅的降低無線電頻率訊號對系統的影響，並且提高資料傳送量。

It is known that radio frequency interference (RFI) degrades the performance of DMT systems for digital subscriber loops. The RFI signal, though narrow band in nature, may be spread to subchannels around the RFI frequencies due to the large sidelobes of the receiving rectangular window. In this thesis, we propose a joint consideration of channel shortening and RFI suppression in the design of time domain equalizers (TEQ). We will design the TEQ by minimizing ISI, channel noise and RFI interference. Simulation results are given to show that the proposed method can considerably reduce interference around the RFI frequencies and increase the transmission rate.