Research on Localization Technology in Wireless Sensor Networks - Advanced Research on Computer Education, Simulation and Modeling - page 396

Fig. 3. Communicate between nodes

Table 1. Location error and packets under different connectivity

connectivity 3 4 5 6 7

Location error% of
radio range

D 100 92 84 76 64

L 67 58 49 40 40

Quantity of sending
packets

D 400 1100 1810 2590 2990

L

360 500 680 860 1410

Table 1 listed the comparisons of the position error and the communication load in
the different connectivity between the DV-HOP algorithm and LDV-HOP algorithm
after increasing the circulation refinement link. When the reference node's percentage
is certain (e.g.20%), the connectivity is relatively small, the position error of the
LDV-HOP algorithm after increasing the circulation refinement link is smaller than
DV-HOP algorithm obviously, the communication load increases along with the con-
nectivity is lower than the DV-HOP algorithm. Therefore, the LDV-HOP algorithm
after increasing the circulation refinement cycle can effectively improve the position-
ing accuracy and reduce the amount of data packets.

4.2 Application of Physics Experiment

The planning of experiment scene: In an area of 50m*50m spacious outdoor plane
domain, taking the CC2430 module with wireless radio function as the node of
WSNs. The stochastic deployment of WSNs was shown in Fig. 4 (a). Let the marked
label 0, l, 2 nodes as the reference node, which occupied 10% of the total nodes, and
the others are unknown nodes. Fig. 4 (b) shows the orientation of distribution of
WSNs position which the red circled round are reference nodes, and the yellow circle
are localization nodes, in process of orientation, through the wireless communication
transfer the gathering data to the coordinator part, and the coordinator communicated
with the host computer through the serial port, finally analyzed the gathering data and
drew the conclusion.
Experimental procedures: First installed IAR Embedded Workbench on PC, then
according to the localization process, node own function and the receiving and dis-
patching information and so on, developed the application procedure in IAR, and
downloaded the program through the USB line to the CC2430 module. Similarly,