Wireless communications are highly error-prone due to inherent wireless channel effects, which include
interference, multi-path fading, and noise. The conventional approach to reducing the effects of frequent channel errors is
to attempt retransmitting the corrupted frames. This solution however introduces long end-to-end delay and channel usage
inefficiency, especially in multi-hop wireless networks. In this work, we introduce the cooperative diversity-based
opportunistic virtual MISO (Multiple-Input-Multiple-Output) approach to alleviate the problem and to improve the overall
performance in multi-hop wireless networks. Our approach allows neighboring nodes to effectively share their available
resources when there is an opportunity to participate. Our observation showed that multi-hop wireless networks consist of
low and high quality links. In the low-quality links, we utilize spatial-diversity property that allows a wireless node with
the highest delivery probability to relay data frames to the next hop. In the high-quality links, when there is more than one
node successfully receiving the same data frame, we utilize space-time block codes (STBC) to extend the transmission
range to deliver data frames up to two hops away. By proposing the approach described above, available network
resources are always utilized to improve the overall performance. OVM provides an effective and simple design solution.
Simulation results show that OVM is able to improve end-to-end network performance by up to eighty-six percent over
Keywords: Spacial diversity, cooperative diversity, opportunistic, virtual miso, mesh, sensor networks.
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