Fingerprint-based positioning in a wireless local area network (WLAN) environment has received much attention recently. One key issue for the positioning method is the radio map construction, which generally requires significant effort to collect enough measurements of received signal strength (RSS). Based on the observation that RSSs have high spatial correlation, we propose an efficient radio map construction method based on low-rank approximation. Different from the conventional interpolation methods, the proposed method represents the distribution of RSSs as a low-rank matrix and constructs the dense radio map from relative sparse measurements by a revised low-rank matrix completion method. To evaluate the proposed method, both simulation tests and field experiments have been conducted. The experimental results indicate that the proposed method can reduce the RSS measurements evidently. Moreover, using the constructed radio maps for positioning, the positioning accuracy is also improved.
In order to improve the performance of RSSI-based radio mapping schemes, the authors of REF represent the distribution of RSSI as a low-rank matrix and generate the dense radio map using a low-rank matrix completion method.
Efficient Radio Map Construction Based on Low-Rank Approximation for Indoor Positioning
Mathematical Problems in Engineering
Mathematics