通訊是發送端透過某種格式來傳遞訊息給接收端來達到某個目的。要讓傳送端與接收端成功建立連線，同步的技術是最基本也是不可或缺的。後四代/第五代網路將結合多種存取技術並朝向多網共存的異質網路邁進。推測未來的相關應用發展大致會以現今的第四代無線通訊系統做延伸，故本論文以第四代無線通訊技術為主，並以異質網路架構為輔，來做橫向的整合應用研究。內容涵括LTE系統的初始同步技術、多路徑訊號的頻率偏移問題以及優化系統降低干擾的資源整合研究。首先針對發展中的LTE系統規格做探討。在實際環境中，由於訊號傳遞的路徑以及通訊設備硬體製造的限制都會帶來訊號損耗或干擾問題。利用LTE系統中專門設計給同步處理用的訊號，加入對實際環境問題的考量提出相關解決方案。之後把探討的架構延伸到異質網路中合作式通訊上。合作式通訊把許多設備互相串連起來，因此傳遞路徑較傳統通訊複雜許多。本論文第二部分討論多對一路徑的情況下，不同的設備因各自的震盪器準確度不同而產生不同的頻率誤差。為了降低硬體的解調成本，利用頻譜估測的方法來處理多頻率誤差的問題。最後，探討隨著各種行動服務及應用的興起而崛起的裝置對裝置通訊技術。裝置間通訊存在各種干擾問題，如何管理異質網路干擾問題將會是未來的發展重點。本論文以資源分配演算法探討裝置間通訊與蜂巢式網路間的干擾問題。;Communication requires a transmitter to use some format to transmit messages to a receiver for some purpose. Synchronization is the fundamental and indispensable technology that successfully establishes this link. B4G/5G wireless networks will combine types of access technologies with the goal of creating coexisting multi-network environments, which are also referred to as heterogeneous networks. Future development will be based on the extension of 4G wireless communication systems. This dissertation comprises horizontally integral research for an application structure based on 4G wireless technology that is assisted using a heterogeneous network. Research topics include the initial synchronization in the Long Term Evolution (LTE) system, the frequency offset problem in multi-link circumstances and resource allocation for suppressing interference and system optimization. The development of the LTE system is discussed first. In practice, signal consumption and interference would arise from the signal transmission path and the limit of device hardware. Related solutions have been proposed through the use of a synchronization signal, which is designed in a LTE system, and practical environments were considered. The discussed iii framework is extended to cooperative communication in a heterogeneous network. Many devices would be strung together using cooperative communication; therefore, transmitting paths are complex compared with conventional communications. In the second part, different devices have different frequency errors due to their individually imprecise oscillators in a multi-input, single-output scenario. The problem of multi-frequency errors was addressed using spectral estimation to reduce the cost of the demodulated hardware. Finally, device-to-device (D2D) communication, which will be used in various types of mobile services and applications, is discussed. Management of the interference problem will be a key issue in the future because there are many types of interferences in D2D communications. In this dissertation, a resource allocation algorithm was proposed to analyze the interference between D2D communication and cellular networks.
