在近幾年來，無線通訊的迅速成長造就了數位無線多媒體應用的需求大增，而且使得高速的資料傳輸變成必要的條件。像是正交分頻多工系統(OFDM)來自於多重載子傳輸技術且能完成高速資料速率在行動通道上的傳送，並可減輕了符元間的干擾(ISI)，且能以低複雜度結構完成了高資料速率的傳輸。最常見的建立於正交分頻多工系統上的應用像是數位音訊廣播(DAB)、數位視訊廣播電視(DVB-T)、IEEE802.11X及無線區域網路(WLAN)等。在正交分頻多工系統裡，指標信號促進調變(PSAM)被使用以傳輸指標去完成可靠的通道估測，適當的指標排列傳輸最多可減輕十倍通道變化所造成的督普勒頻率偏移。在這篇論文，我們將使用指標通道估測技術加上內插法去分析不同的指標排列型式的位元誤差率(BER)，並且我們提出兩種有效的
指標排列規劃搭配內插法以減輕督普勒效應在無線行動正交分頻多
工系統所造成的誤差，然後比較其各種指標排列形式的性能並且評估其適用性。

In recent years, the rapid growth of digital wireless communication needs to be increased for high speed data transmission. As OFDM comes from multi-carrier transmission technique. It alleviates ISI and achieves high data rate transmission with low complexity. There are three OFDM-based systems as DAB, DVB-T, and WLAN. In OFDM, the coherent modulation requires the channel estimation, but its receiver structure is more complex than differential modulation. PSAM is used to achieve reliable channel estimation by transmitting pilot along with data symbols. In this thesis, we will analyze different pilot arrangement patterns in terms of BER and propose a new pilot scheme for transmitting pilot symbols in wireless OFDM systems,
and comparing with their performance.

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