60 GHz光載微波訊號系統之單邊帶單載波調變方式的效能研究

Abstract

為了因應對通訊的資料傳輸的高需求，60GHz光載微波傳輸系統提供可傳輸用的免費高頻寬，此外，隨著通訊技術的發展，訊號可以同時在時域及頻域上處理，其中單載波訊號產生搭配頻域等化器(SC-FDE)結合了傳統在時域上產生訊號有較低的峰均值功率比，以及在頻域上解調訊號可以像正交分頻多工一樣有較低複雜度的優勢，為了研究在時域上及頻域上處理訊號的優勢與缺點，我們使用單變帶單載波(SSB-SC)訊號(其在基頻即是無載波調幅與相位調變(CAP))搭配頻域等化器以及時域上的決策回饋等化器(DFE)去分析其效能，在頻域等化器中改變快速傅立葉轉換的長度，而在決策回饋等化器裡操作前向濾波器(FFE)及回饋濾波器(FBE)的記憶體長度比較效能的變化。此外，另一種像循環字首(CP)的技術稱為獨特字首(UW)，我們藉由在頻域等化器跟決策回饋等化器搭配單頻帶單載波系統分析了CP跟UW之間的效能。

For the high demand of communication, Radio-over-Fiber in 60GHz provide broad free bandwidth for transmission[1]-[2]. Besides, as the development of communication technology, signal can be processed from time domain to frequency domain[3]-[4]. Single carrier with frequency domain equalizer (SC-FDE) combine the advantage of generating signal in time domain as traditional single carrier, (which lead lower PAPR) and decoding in frequency domain like orthogonal frequency-division multiplexing (OFDM), (which has lower complex to compensate ISI)[8-9]. For researching the relationship between decoding in time domain and frequency domain. We use single-sideband single carrier (SSB-SC)[10]. To investigate the performance of frequency domain equalizer (FDE) and decision feedback equalizer (DFE)[11], we compare the performance with different FFT size with FDE and different taps with DFE. Furthermore, the other prefix like cyclic prefix (CP) is unique word (UW), we analysis the performance between CP and UW for FDE and DFE in SSB-SC system [13].