Cooperative transmission range extension for duty cycle-limited wireless sensor networks

In this paper, we discuss how cooperative transmission (CT) can provide better services and/or lower the initial cost compared to non-CT in wireless sensor networks. To see the performance of CT and non-CT in both battery operated and energy harvesting networks, we look at the duty cycle instead of the energy and convert the conventional non-CT and CT routing protocols to their duty cycle versions. We calculate the duty cycle limit, which is used as a performance bound in our network simulation, based on a building management application. Through the network simulation, we show that when CT is used appropriately, it allows more sensor nodes to be supported by a single gateway node, thereby lowering initial cost, and it can provide more frequent data gathering.