LAUSR

Data dissemination is an essential application in Internet of Things (IoT) network. It is generally relayed hop-by-hop due to the limitation of the communication distance of IoT devices. However, multi-hop transmission increases dissemination time, especially in a low duty-cycle network. Channel contention is another factor result in long delay, because most of IoT devices and Wi-Fi equipment work within the same bandwidth (2.4 GHz). To reduce the transmission delay of data dissemination, our group proposes a method of multi-channel transmission simultaneously (MCTS) using no-feedback fountain code. Instead of terminating sending data by feedback as a traditional fountain code protocol, in the MCTS, the sink node pours a certain amount of packets into the network according to the distance of object nodes to guarantee reliable transmission. By making use of channel encoding, the data to ZigBee nodes can be carried by some subcarriers of Wi-Fi in multiple ZigBee channels simultaneously when Wi-Fi sends itself data. This method technically avoids the delay from channel contention. Compared with the flooding method, the delay of the MCTS sending data from the sink node to all ZigBee nodes is decreased to 1/4.