Effect of channel bonding and parallel data transmission with IEEE802.11n wireless LAN in a small sewer pipe

Sewer pipe deterioration is one serious issue in many countries and sewer pipe inspections are essential for maintaining sewer systems. There are various sewer inspection methods such as visual check, boat-type video cameras, remote robots with or without wired connection. They, however, suffer from many problems such as high labor, monetary cost of robots, long waiting time when using boat-type video cameras. Towards a low-cost, safe, and near real-time inspection of sewer pipe, we have proposed a drifting wireless camera/sensor nodes-based inspection method and identified the radio communication range in a small sewer pipe (200 mm diameter) with off-the-shelf 2.4 GHz and 5 GHz IEEE 802.11b/g wireless LAN devices. In this paper, we investigated the effect of channel bonding introduced by IEEE802.11n and parallel data transmissions using multiple interfaces on improving the performance of wireless communication in small pipes. Measurement results revealed that can be achieved by using channel bonding when the communication distance is less than 4 m and placement of antennas is essential for ensuring a wider communication range. We also discuss a strategy for transmission between an access point and a camera/sensor node moves in small pipes.