CHEN Lijun and MAO Yingchi have proposed a topology
control of wireless sensor networks under an average degree
constraint[4]. In the precondition of the topology connectivity
of wireless sensor networks, how to solve the sparseness of the
network topology is a very important problem in a large
number of sensor nodes deployed randomly. They proved their
proposed scheme can decrease working nodes, guarantee
network topology sparseness, predigest routing complexity and
prolong network survival period.