A distributed area coverage algorithm based on delayed awakening in wireless sensor networks

The area coverage technology is one of the basic technologies of wireless sensor network, and is mainly concerned about how to prolong network lifetime on the basis of meeting area full coverage and network connectivity. The existing distributed area coverage algorithms often have phenomenon of coverage loopholes and ignore connection issue. Otherwise, they have phenomenon of nibble and shorten network lifetime. Therefore, connectivity issue is analyzed for distributed area coverage algorithms and the connectivity critical condition to ensure area full coverage and network connectivity is proposed. It provides connectivity guarantee for area coverage of active nodes set. On this basis, a distributed area coverage algorithm based on delayed awakening scheme is proposed. It applies time round mechanism, and carries out coverage decision judgment through exchanging local state information with neighbor nodes. So, the network topology need not be known in advance. Active nodes set select scheme based on delayed awakening selects active nodes set by using circle intersection coverage evaluation method and delayed awakening method based on distance threshold, and ensures fully covered area and avoids the phenomenon of coverage loopholes, and reduces the phenomenon of nibble. Simulation results show that compared with the existing distributed area coverage algorithms, this algorithm can prolong the network lifetime on the basis of meeting users' sense demands.