Multipath virtual sink architecture for wireless sensor networks in harsh environments

Wireless sensor networks are expected to be deployed in harsh environments characterized by extremely poor and fluctuating channel conditions. With the generally adopted single-sink architecture, be it static or mobile, such conditions arise due to contention near the sink as a result of multipath data delivery. The compactness of sensors with limited energy resources restricts the use of sophisticated FEC or ARQ mechanisms to improve the reliability of transmissions under such adverse conditions.We propose a novel virtual sink architecture for wireless sensor networks that mitigates the near-sink contention by defining a group of spatially diverse physical sinks. Reliability and energy efficiency is achieved through multipath data delivery to the sinks without the need for sophisticated FEC or ARQ mechanisms. This architecture is especially suitable for indoor environments, where channel conditions are harsh due to severe multipath fading, as well as emerging applications like underwater sensor networks where the predominant physical layer is acoustic communications, which is characterized by long propagation delays and severely fluctuating link conditions. We present our proposed architecture and demonstrate its efficacy using mathematical analysis.