  A new method for estimating the relative positions of location-unaware nodes
from the location-aware nodes and the received signal strength (RSS) between
the nodes, in a wireless sensor network (WSN), is proposed. In the method, a
regularization term is incorporated in the optimization problem leading to
significant improvement in the estimation accuracy even in the presence of
position errors of the location-aware nodes and distance errors between the
nodes. The regularization term is appropriated weighted on the basis of the
degree of connectivity between the nodes in the network. The method is
formulated as a convex optimization problem using the semidefinite relaxation
approach. Experimental comparisons with state-of-the-art competing methods show
that the proposed method yields node positions that are much more accurate even
in the presence of measurement errors.
