8. Conclusion
In the range free WSN, the localization of nodes is proposed by many
models. Here, DV-Hop algorithm rules over other algorithms due to its
simplicity only. But it (DV-Hop algorithm) is unable to spot a node with
high accuracy. So it (DV-Hop algorithm) highlights a gap for a method to
localize with high precision. To improve localization accuracy, the
proposed model ODR spots the location of unknown nodes with high
accuracy and without any requirement of additional hardware. Also, ODR
improves the localization accuracy without any additional burden on the
network in terms of message communication. The paper highlights the need
for Euclidean distance to determine the distance between the anchor and
unknown nodes. Here ODR paves a way to find out Euclidean distance
(between the anchor and unknown nodes) approximately and establishes the
proposed model to localize with high accuracy. Although the exact
Euclidean distance is not obtained an essential error value in this
distance (between the anchor and unknown nodes) is defined and estimated
with the help of optimized linear programming.
The other algorithm IDV improves the localization but at the cost of
additional computational requirements due to the hop size correction
factor. The suggested model ODR improves the localization results
further better than both DV-Hop and IDV algorithms but no extra cost is
needed to improve the hop size. The communication requirements among the
nodes are the same in ODR, DV-Hop, and IDV.
Hence the paper is able to establish analytically as well as
experimentally the proposed method ODR to localize unknown nodes with
more accuracy by estimating approximate Euclidean distance. Also, it
(i.e. ODR) can contribute a method to improve the hop size without any
extra cost. Moreover, through simulation results and analytical
reasoning ODR establishes itself as the least affected algorithm by the
network variables (i.e. anchor nodes’ percentage, communication range,
and nodes’ density) in comparison to its other contenders- DV-Hop
algorithm and IDV.
In the future, the localization should be further improved by reducing
the values of WSN constraints’ limits.