The existing classic anchor-free localization (AFL) algorithms have relatively large localization error and tend to get local optimal value.Therefore
a two-phase improved anchor-free localization (I-AFL) algorithm with phase advantages is proposed.In the first phase of the I-AFL algorithm
a precise coordinate system is established through hop-count quantization
which uses the measured distance information to break the length of node communication radius into multiple hops.The second phase of the I-AFL algorithm uses an adaptive mass-spring optimization algorithm to optimize the node position and prevent the position from falling into local optimum value during the iterative optimization process.Both the theoretical analysis and simulation results show that compared with the traditional algorithm