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From locating techniques in the wireless sensors networks two groups based on harbor and without it can be referred
to. Firstly, the harbor nodes distribute the local information in the network and through that the average distance between
two groups or the average length of a step is identified. Non-harbor nodes know the shortest path as the number of steps
to each of the harbors and determine their distance to the harbors by understanding this average step length and using this
estimation compute their location distance. Firstly, the network nodes are clustered. Each harbor is a cluster head and the
cluster members using information derived from this cluster head begin locating. This process starts by the nodes located
in the common field between two clusters. Although algorithm comparability based on harbor is increased by the nodes
clustering, but the algorithm precise and efficiency is still dependent on the number of harbor nodes. Using harbor in all
of the conditions causes its usage limitation in the wireless sensor networks.
Regarding the algorithms without needing to harbor, algorithm is the first case. This algorithm has invented a new
method to make a local graph in the network which is applicable in computing the relative features of nodes. Firstly,
each node makes a graph with its own axis. Then the general graph of network is made and each node changes its
coordinates by using an algorithm. Because of the current limitations in the trigonometry method used in this algorithm,
the computed coordinates are not reliable and face difficulties in many cases. The other algorithms being needless to
harbor try to use another methods instead of trigonometry methods in locating.
For instance, among these methods, those ones based on graph drawing or mass and coil algorithms can be referred
to. These kinds of algorithms take much time and use a lot of energy. In order to upgrade the algorithm results quality
and prevent the fault distribution, we define a secondary parameter called the computed location accuracy. This
parameter indicates location accuracy and can be a value between zero and one.
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