| Authors |
H. Ichikawa, S. Sato, H. Okada, T. Wada, K. Kobayashi, M. Katayama |
| Title |
Evaluation of Time Asynchronous of Display-Camera Links for Visible Light Communications |
| Authority |
RISP International Workshop on Nonlinear Circuits, Communications and Signal Processing (NCSP), pp.121-124 |
| Summary |
In visible light communications (VLCs) using a liquid crystal display (LCD) as a transmitter (Tx) and a camera of a mobile device as a receiver (Rx), time asynchronous of display-camera links occurs so that Tx and Rx clocks operate independently each other. In this case, the Rx may capture a mixed image of two consecutive frames in a constant ratio if the transmitting rate and the frame rate of the image sensor are same. Also, due to the sequential-readout structure of a CMOS image sensor, each scanline of the captured image is exposed at a different time. Then, each scanline of the captured image has different mixed ratios of two consecutive frames, resulting in the rolling shutter effect. These issues cause the degradation of the communication quality because they complicate the derivation of the transmitted data sequence from the captured image. In this paper, we simulate the effect of time asynchronous and rolling shutter by modeling a VLC system. From the simulation, we clarify that shorter exposure time can reduce the degradation of the above
issues. Then, we propose a strategy suitable for VLC under time asynchronous. We implement the proposed strategy and evaluate its performance by experiment. |
| 年月 |
2017年3月 |
| DOI/Handle |
|
| 開催場所 |
Guam, USA |
| 研究テーマ |
可視光通信／光無線通信
|
| 言語 |
英語 |
| 原稿/プレゼン資料 |
 /  (ローカル限定) |
