在蜂巢式行動通訊統中建立一個無線連線涉及了下鏈已知序列模版與基地台之間的搜尋與同步。尋找的過程，通常稱之為基地台搜尋（cell search）。在資料可以傳遞之前，必須先尋找出行動裝置處於哪一個基地台的服務範圍內才能建立連線。基地台搜尋一般是藉由引導序列（preamble sequences）的比對來達成。每個基地台有特定的引導序列，而行動裝置藉由比對收到的引導序列和資料庫中的序列來決定要和哪一個基地台進行連線。因此，所使用的引導序列會嚴重地影響基地台搜尋的效能。在這份論文裡面，我們提出一種從里德米勒碼（Reed-Muller codes）產生類完全互補碼（quasi complete complementary codes）的方法。因為類完全互補碼有很好的自相關及互相關特性，在這份論文中我們提出了三種使用類完全互補碼的引導結構。另外，產生出來的類完全互補碼有較低的峰值對均值功率比（peak-to-average power ratio），因此適合使用在正交分頻多工（orthogonal frequency division multiplexing）系統中。基於類完全互補碼富有代數結構的特性，我們也提出了有效率的編碼及解碼演算法。相較於全球互通微波存取（Worldwide Interoperability for Microwave Access）系統中使用電腦搜尋產生沒有結構的偽雜訊（pseudo noise），使用基於類完全互補碼的引導可以大幅降低編碼以及偵測的運算複雜度。電腦模擬的結果顯示，使用基於類完全互補碼的引導可以和使用偽雜訊引導有相同的搜尋效能。

Establishing a radio link in cell-based mobile communication
systems involves searching and synchronizing the downlink known
pattern of sequences associated with the base stations. The
searching process, often referred to as cell search, is usually
done with preamble sequences. Therefore, the performance of
cell search depends greatly on the employed preamble sequences. In this
thesis, we propose a construction of quasi complete complementary
codes (QCCCs) from Reed-Muller (RM) codes. Since the constructed
QCCCs have good auto-correlation and cross-correlation properties,
three preamble structures based on QCCCs are proposed in the thesis.
Furthermore, the constructed QCCCs have
low peak-to-average power ratios (PAPRs) and proposed in this thesis are hence
suitable for use in orthogonal frequency division multiplexing
(OFDM) systems.
Efficient encoding and decoding algorithms are also proposed based on the rich algebraic structures of QCCCs.
Compared with the computer-searched pseudo noise (PN) sequence preambles employed in the WiMAX system,
great complexity reduction in encoding and detection can be obtain for QCCC-based preambles.
Simulation results also show that for cell search the QCCC-based preambles
perform as well as PN preambles.

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