SADR: A Single Anchor and Dead Reckoning Based Fusion Indoor Positioning Algorithm

The dead reckoning (DR) is widely used for indoor positioning because it does not rely on external information, but it has the disadvantage of not being able to give an initial position and the problem of error accumulation. When the number of anchors is greater than two, the ranging-based multilateral positioning algorithm can provide the positioning position without accumulated error. However, in the practical application of indoor positioning, it is very costly to guarantee coverage with at least three anchor points at each location. In response to the shortcomings of the two indoor positioning methods mentioned above, this paper discusses for the first time how to effectively integrate single anchor and DR for indoor positioning, namely SADR. By combining the range information of a single anchor with the distance information of DR, SADR can not only provide the absolute position of the target to be located but also avoid the accumulation of positioning error and the need for more anchor coverage. The contribution of SADR mainly has two aspects: on the one hand, two specific initial positions and position refinement mathematical models are provided for the positioning problem proposed in this article; On the other hand, the existing least squares method and gradient descent method are used respectively to solve the above mathematical problems. The simulation results show that the average positioning error of SADR is about 1.4 m, the standard deviation of ranging and DR is 0.6 m, and 80% of the poslitioning error is less than 2.5 m.