LEDアレイと高速度カメラを用いた可視光通信のための優先度重畳符号化

摘要

In this paper, we discuss on visible light communications using an LED array as the transmitter and a highspeed camera as the receiver. A challenge is that the longer the distance between the transmitter and the receiver, the more reduction in the resolution of the receive image occurs. To solve the problem, we allocate high priority data to low frequency components of spatial frequency. Then, we can receive high priority data even if the receiver is far from the transmitter. For that, we have used the Wavelet transform in our previous researches. However, the conventional scheme limits the number and the disposition of LEDs which can be allocated data. In other words, the hierarchical coding using the Wavelet transform has a low degree of freedom of design. In this paper, to improve a degree of freedom of design, we propose the overlay coding which does not limit the number and the disposition of LEDs.%本稿では送信機にLEDアレイ，受信機に高速度カメラを用いた可視光通信を考える．送受信機間の距離が長くなるほど受信画像の解像度が劣化する問題に対して，画像の空廟周波数が劣化しにくい低周波成分に優先度の高いデータを割り当てることで，距離が長くても優先度の高いデータの取得を可能にした．その際に従来用いていたウェーブレット変換はデータを割り当てるLEDの数や配置が制限されるなど，設計の自由度が低い．そこで設計の自由度の向上を目指して，データを割り当てるLEDの配置や数に制限のない優先度重畳符号化を提案し，その特性を評価する．