A low delay MAC protocol for lake environmental monitoring based on UASN

For the lake environment monitoring, the underwater acoustic sensor networks are often used, in which the transmission medium is acoustic. Different from the radio channel on the land, the underwater acoustic channel has the characteristics of low acoustic signal propagation speed, wide range and narrow bandwidth. Considering these features, the topology for the lake environment is designed. Then a low delay MAC layer protocol LDM-U is proposed which improves the handshake processing and the backoff mechanism between the neighbor nodes. Simulation results show that the proposed protocol can reduce the transmission delay caused by handshaking effectively, and increase the throughput.