2 × 2多天線輸入多天線輸出正交分頻多工60GHz光載微波訊號系統使用低取樣率類比數位轉換器偵測

Abstract

隨著近代科技的快速發展，手持式行動裝置與線上多媒體服務已成為時代的趨勢，例如國際運動節目直播、高畫質電視及影音以及虛擬實境視覺感官體驗。通訊系統為了因應龐大的資料傳輸量而發展出更新的應用層面與技術，包括資料接收處理複雜度、延遲問題以及提高資料傳輸速率已是必須即刻解決的問題。 增加頻譜使用效率以及擴大射頻無線頻寬是增加資料傳輸速率的兩大關鍵，然而在寬廣的無線頻寬系統中發現接收端需要高取樣率類比數位轉換器接收訊號以及大量的數位訊號處理，造成系統接收端成本提升。 因此提出了應用在多天線輸入多天線輸出正交分頻多工訊號射頻光纖網路系統(MIMO-OFDM-RoF)中新穎的偵測方式。先經由預先處理(Pre-processes)技術，處理後的訊號經由射頻光纖網路系統傳輸，接著被多個低速奈奎斯特取樣率類比數位轉換器(sub-Nyquist sampling ADC)接收。此偵測方式不需要多天線輸入多天線輸出解調以及複雜的數位訊號處理。 基於接收時採用156.25 MHz取樣率的類比數位轉換器，2 x 2多天線輸入多天線輸出正交分頻多工無線射頻光纖網路系統可成功達成47.06G bits 每秒的傳輸速率。

With the rapid development of modem technology, handheld mobile device and online multimedia services have become the trend in life. Such as international sports programs live, high-definition video and audio, and virtual reality in visual sensory experience. In order to cope with huge data transmission, communication system needs to be updated about its technology and application level, including the cost of data reception, processing complexity, latency and data rate. Increasing the efficiency of spectrum and expending the radio frequency band are the keys to increase to increase data rate. However, in the wide wireless bandwidth, the receiver needs high sampling rate analog-to-digital converter to receive signals, this causes high costs about device and complex digital processing after receiving. Therefore, a novel detection method is proposed in the orthogonal frequency division multiplexing radio-over optical fiber network system (OFDM-RoF). Besides, it also supports multi-input multi-output (MIMO) technology. Using pre-processing technology, after pre-processing, the pre-processed signals go through radio-over optical fiber system and received by ADCs with sub-Nyquist sampling. This detection method doesn’t require not only complex digital signal processing at receiver but also MIMO demodulation if supported MIMO technology. Based on using only 156.25 MHz sampling rate of ADCs, 47.06- Gbs 2×2 MIMO-OFDM-RoF transmission was successfully demonstrated.