船内電力線線路の遅延および減衰特性

摘要

電力線通信技術の産業用途の一つとして，船内LANがある．本稿では，船舶内居住区の100V系統（4隻）および冷凍コンテナ船の440V系統（2隻）で調査した伝達関数から遅延プロファイルを求め，遅延特性を評価している．その結果遅延特性は，ケーブル長と分電盤内部の遅延スプレッドをパラメータとする一次関数で近似できることを述べている．また，遅延時間の累積分布を求め，船舶で使用する場合の，OFDM方式のガードインターバル値について検討している．さらに，減衰特性の近似式をもとに，コモンモード伝送がディファレンシャルモードよりも有理になる領域を明らかにしている．%Power-line Communication(PLC) based local area network(LAN) in ships are one of the promising applications of the PLC technology. In this paper, the delay profiles have been analyzed from the transfer function of 100V power-line channels of residence area in ships and that of 440V power-line channels for reefer containers, which had been measured by the authors. It was found that the characteristics of the delay spread were able to be approximated by a liner function of which the parameters were the length of cable and the delay spread in distribution panels. The cumulative distribution of delay tune has also been calculate, and the required guard-interval value for the OFDM system in ships has been shown. In addition, the area where the signal attenuation of common-mode transmission becomes less than that of differential-mode has been studied from the channel model of attenuation.