This paper focuses on a road-to-vehicle visible light communication(VLC)system using LED traffic light as the transmitter and camera as the receiver. The traffic light is composed of a hundred of LEDs on two dimensional plain. In this system, data is sent as two dimensional brightness patterns by controlling each LED of the traffic light individually, and they are received as images by the camera. Here, there are problems that neighboring LEDs on the received image are merged due to less number of pixels in case that the receiver is distant from the transmitter, and/or due to blurring by defocus of the camera. Because of that, bit error rate(BER)increases due to recognition error of intensity of LEDs. To solve the problem, we propose a method that estimates the intensity of LEDs by solving the inverse problem of communication channel characteristic from the transmitter to the receiver. The proposed method is evaluated by BER characteristics which are obtained by computer simulation and experiments. In the result, the proposed method can estimate with better accuracy than the conventional methods, especially in case that the received image is blurred a lot, and the number of pixels is small.%本稿では，送信機にLED交通信号機,受信機に車載力メラを用いた路車間可視光通信においてLED信号機内の各LEDを個別に制御して2次元の明暗パターンとしてデータを送信する場合を想定する.送信機と受信機の距離が遠く送信機像のピクセル数が少ない場合や,画像のボケが大きい場合にLED輝度値の認識精度が低下する.そこで，送信機と受信機間のチヤネル特性を線形としてモデル化し，その逆問題を解くことでLEDの輝度値をより正確に推定する手法を提案する.提案手法の有用性を検証するために計算機シミュレーションによるビット誤り率特性の評価と，LEDアレイとカメラを用いた実験を行った.その結果，提案手法は従来手法に比較して画像のボケが大きい場合や，ピクセル数が少ない場合に推定精度が良好であることが確認された.
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