Error control strategies for transmit-only sensor networks: A case study

Wireless sensor networks using transmit-only sensor nodes are a promising new approach for applications such as environmental monitoring because they can provide high network scalability and long life-time at low cost. But achieving reliable data delivery in a transmit-only network is a challenging problem because there is no feedback channel for reporting lost or damaged packets. Taking a systems approach, this paper identifies three specific error control strategies that are applicable in this design space. The strategies are drawn from the areas of temporal diversity, spatial diversity and coding-based methods. An empirical investigation of these strategies is performed using two case study deployments in indoor and outdoor settings, running from two weeks to several months. In both case studies data replication in successive packets and receiver diversity performed best. In most cases, but not all, coding-based methods offered a poor balance between overhead and efficiency.