An Improved IDW Location Fingerprint Library Construction Algorithm with Joint AP Location Constraints

In location fingerprinting algorithms, we need to collect location fingerprint data at different scales to construct offline location fingerprint databases, which requires significant labor costs. Therefore, an improved inverse distance weight (IDW) interpolation algorithm based on the location constraints of wireless access points (APs) is proposed to perform interpolation calculations to construct a new offline fingerprint database in the case of sparse collection points. The circular constraint is first introduced to improve the traditional IDW algorithm, and then the algorithm is improved based on the spatial characteristics of RSSI data. The experimental results show that the proposed algorithm has a good improvement on the traditional IDW interpolation algorithm in terms of accuracy of fingerprint database establishment, while maintaining a good performance in indoor localization.