Ranging error correction based on a prior error model

Wireless technology provides accurate positioning in indoor environments using time of arrival (TOA) based ranging techniques. However, the positioning accuracy is degraded due to the ranging errors caused by multipath and non-line-of-sight (NLOS) propagation. In this paper, a ranging error correction method is proposed to improve positioning performance. A TOA ranging error model (TREM) is built to provide the prior information for ranging error correction first. The mean value of TREM within a certain interval is used as the ranging error correction value (RECV). As the RECV may be unreasonable sometimes, we adjust it according to the actual positioning situation and then exploit the final RECV to correct ranging data. The experimental results show that the proposed method could well reduce ranging errors and the positioning performance is obviously improved when using corrected ranging data.