單載波調變與多天線輸入多天線輸出傳輸技術應用於60 GHz光載微波無線訊號系統

Abstract

互動式多媒體的快速發展，導致新的無線網路服務不斷推陳出新，對於傳輸速度的要求也逐漸升高，帶動了multi-Gbps無線傳輸技術的發展。然而，60 GHz的免授權頻段其頻寬限制在7 GHz，並且60 GHz的微波訊號在空氣中有著非常大的衰減，較適合短距離的無線傳輸。因此，60 GHz的光載微波無線訊號系統搭配上空間多功的MIMO技術是一個非常可實現的一個方法，提供一個寬頻、覆蓋範圍廣以及機動性兼具的服務。 在此篇論文中，藉由頻域等化器實現2 x 2 MIMO技術，提高頻譜使用效率達成傳輸資料倍增的效果。我們在實驗上成功傳輸60GHz 頻段上7 GHz免授權頻寬的16-QAM MIMO 單載波訊號，傳輸速度達到2 x 13.575 Gb/s，在經過25公里的單模光纖和3公尺的無線傳輸以後，訊號品質幾乎沒有改變。

The rapid growth of data rates of new wireless applications led by interactive multimedia services is driving the need for multi-Gbps wireless communication technologies in the near future. However, the bandwidth of the license free spectrum at 60 GHz is limit to 7 GHz and 60-GHz millimeter-waves have very high propagation losses rendering them more suitable for short-range wireless links (~10m). Therefore, 60-GHz radio-over-fiber (RoF) system with spatial-multiplexing MIMO technology is a promising candidate to provide broadband service, wide coverage, and mobility. In this these, 2 x 2 MIMO technique is realized by frequency domain equalizer (FDE) to improve spectrum efficiency doubling the data throughput. We experimentally demonstrate 2 x 13.575 Gb/s 16-QAM MIMO single carrier signal transmission within 7-GHz license-free bandwidth at 60-GHz band. The power penalty is negligible after transmission over 25-km single mode fiber and 3m wireless distance.