無線HDMI 系統之合作式通訊

Abstract

無線HDMI系統主要是用來在短距離傳送解析度高達1,920 x 1,080p未經壓縮的高解析視訊、音訊及資料。但是高畫質、低延遲時間的高畫質資料，需要很高的資料率(data rate)。舉例來說：要傳送未壓縮的1080p的資料，需要的資料率差不多為4Gbps。 在無線HDMI系統上，訊號傳輸會面臨三種挑戰。第一：有很大的路徑遺失(Path loss)；第二：高指向性(directivity)，也就是說波束寬度(beamwidth)很窄；第三：穿透能力(penetration)低。這樣使得三個問題產生：(1)高傳送功率，(2)高指向性，(3)需要直視傳播(Line-of-Sight, LOS)的特性。前面兩個問題，可以用智慧型天線技術來解決，卻無法有效解決直視傳播的問題。而在這篇論文中，將探討合作式通訊技術來解決非直視傳播(NLOS)的問題。 合作式通訊是一種實現空間分集來對抗衰落的技術，藉由一根天線的終端和網路內的另一個或多個終端互相合作，而形成虛擬的陣列天線，因此而獲得空間分集的增益效果。本論文主要目的即是研究合作式通訊在無線HDMI系統中，如何應用在LDPC上，並做出LDPC效能的評估，結果顯示合作式通訊可有效的提高無線HDMI系統中LDPC在衰落通道的性能表現。

Wireless HDMI system is developed to transfer uncompressed HD video, audio, and data in short distance, which dpi can reach 1,920 x 1,080p. However, content with highest quality and low latency require very high data rate. For example, to deliver uncompressed data with 1080p takes about 4Gbps data rate in average. Upon Wireless HDMI system, there are three major challenging dimensions existing in delivering signals, which are “Path Loss, Directivity, and Penetration,” and resulted in three critical problems, high transfer rate, high directivity, and requirement of Line-Of-Sight. To solve the first two problems, we can use Smart Antenna as an effective tool. But on the other hand, we still can’t overcome the problem of requirement of Line-Of-Sight. As a result, we are going to discuss solving problem of NLOS by using Cooperative Communication technology in this context. Cooperative Communication technology is used to realize space diversity against fading channel. By connecting one antenna terminal with another one or even several antenna, it can advanced create a virtual array antenna. And gain the benefits of space diversity effects furthermore. The primary purpose in my research is to explore how Cooperative Communication in Wireless HDMI System applied in LDPC, and evaluate the efficiency of LDPC. The outcome proposes that Cooperative Communication can effectively elevate LDPC performance in fading channel within Wireless HDMI Systems.