Fig. 1. An example of communication between anchor node and unknown nodes

Fig. 2. An example for area of near-degree. (a) r=R3; (b) r=2R3; (c) r=R

Fig. 3. Procedure of IDV-Hop-DPDEL

Fig. 4. Node distribution

Fig. 5. Localization error of each unknown node based on IDV-Hop-DPDEL and DV-Hop

Fig. 6. Localization error of hop distance correction

Fig. 7. Localization error of DPDEL algorithm

Fig. 8. Localization error of IDV-Hop-DPDEL algorithm

Fig. 9. Average localization error with variation of ratio of anchor nodes

Fig. 10. Average localization error with variation of communication radius of sensor nodes

Fig. 11. Average localization error with variation of total number of nodes