On the basis of study of approximate point-in-tetrahedron 3D（ APIT—3D） localization algorithm

present an improved localization algorithm

called APIT—VP. The new algorithm aims at solving the problem of low precision and low coverage rate of localization in APIT—3D algorithm when distribution of nodes is not uniform. To some extent

it also avoids misclassification errors including OutToIn as well as InToOut in PIT—3D test. At the same time

to reduce the computational complexity and to reduce energy consumption

the new algorithm uses space division and segmentation method based on the median plane instead of the original grid scanning algorithms. Simulation experimental results indicate that the positioning coverage rate is up to 90 % and positioning error is controlled about 25 % when 300 nodes are randomly deployed in 100 m × 100 m × 100 m 3D area scenarios

in addition

the computational complexity is effectively reduced compared with APIT—3D algorithm.