採用先進的訊號處理技術提高基於太陽能電池作為接收器 之可見光通訊系統的傳輸性能

Abstract

使用發光二極體(Light emitting diode，LED)的可見光通訊系統(visible light communication，VLC)可以同時提供照明和通訊。太陽能電池具有靈活性高、成本低，易於使用和無需外部電源等特點；因此使用太陽能電池作為可見光通訊系統接收器是具有發展性的。它可以將VLC的訊號轉換成電，為接收端設備充電，適用於成本敏感的物聯網。然而，使用太陽能電池作為VLC接收端是具有挑戰性的，在它有限頻寬、接收訊號失真等問題下，使用狀況受到限制。 本論文主要探討三種改善方式及一種應用。三種改善方式分別為：Manchester Pre-distortion解決了太陽能電池直流基線飄移及訊號失真問題，因此數據速率的提高可以達到50倍。MIMO用於多組傳輸、接收端干擾問題。太陽能電池增設並聯電阻可在沒有訊號處理的情況下增加頻率響應。而可見光通訊的應用為除了通訊用途之外，我們提出了室內定位系統應用，未來配合物聯網可延伸更多應用。

Visible light communication (VLC) using light emitting diodes (LEDs) can be used in illumination and communication.Solar cells with high flexibility, low cost, easy to use, no external power supply, etc.; thus, using solar cells as VLC receiver is promising.It can convert the light signal into electricity, and charge the receiving device for Internet of Things. However, the use of solar cells as receiver is challenging, under its limited bandwidth caused distorted signal and other issues, the application is limited. This thesis discusses three kinds of improvement methods and one application. The three improvements are: Manchester Pre-distortion solves the problem of DC baseline drift and signal distortion of solar cells, so the transfer rate can be enhanced by 50 times.MIMO is used interference of multiple sets of transmission and receiver. Parallel resistor of solar cells can increase the frequency response without signal processing. Besides communication, we proposed the application of indoor positioning system and can be applied in more applications in the future.