近幾年來隨著行動裝置的普及，行動通訊的技術也不斷更新，下個世代的5G行動通訊也已經箭在弦上，但系統除了基地台到行動通訊用戶端這段由無線電通訊，另外還包含了中央機房到基地台這段是由光纖所傳輸的，而本篇論文所考慮的是整個系統設置的架構以及成本效益。
由於第五代行動通訊技術(5th generation mobile networks, 5G)是現有4G行動通訊技術的延伸，在無線行動通訊上依然採用正交分頻多工(Orthogonal Frequency Division Multiplexing, OFDM)技術提升訊號的頻譜效益。而在光纖傳輸上，使用偏振態多工(Polarization Division Multiplexing, PDM)也可以提升傳輸資料容量。另外，由於5G採用的是毫米波的無線電頻段，對於在空氣中以及遇到障礙物時的衰減也是非常嚴重，也必須部建相當大的基地台數目，在這些基地台的涵蓋之間，合作式通訊(Cooperative Communication)也是未來有希望被5G採用的技術，用來改善基地台邊界的訊號品質。
本篇實驗模擬建構了OFDM訊號在光纖中以PDM技術傳輸在分別傳到不同天線(Radio access unit, RAU)利用光學直接解調進行光電轉換再升頻到毫米波傳輸後由天線(User Equipment, UE)接收解調，量測經過了25公里的單模光纖和30 GHz的無線電所得到的訊號表現。透過比較各自單路天線傳輸和同時兩路天線傳輸時的情況，以及兩路天線的涵蓋範圍和角度對訊號錯誤率的影響，驗證整合了CoMP-PDM-OFDM的合作式光纖無線通訊整合。

In recent years, the popularity of mobile devices has growing rapidly, and so as our mobile communication technology, the next 5th generation mobile networks on the verge of commercial operation. But the system is not only the base station to the user device but also the central office to the base station. The whole system’s structure and affordability is discussed. Based on the 4G system, the Orthogonal Frequency Division Multiplexing (OFDM) is utilized, and the use of Polarization Division Multiplexing (PDM) can also increase the spectral efficiency and data capacity is doubled. Cooperative Communication is another technique that suitable for those who near the edge of base station, which may able to have a better signal performance.
This paper simulates a Radio over Fiber (RoF) network architecture. In the experiment, the optical IF signal of CoMP-PDM-OFDM is employed. By the use of STBC, two type of CoMP are proposed - MISO & MIMO. The influences of BER for different position and angle of antenna is also being discussed. 

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